QDir Class Reference

The QDir class provides access to directory structures and their contents.

  1. #include <QDir>

Note: All functions in this class are reentrant.

Detailed Description

The QDir class provides access to directory structures and their contents.

A QDir is used to manipulate path names, access information regarding paths and files, and manipulate the underlying file system. It can also be used to access Qt's resource system.

Qt uses "/" as a universal directory separator in the same way that "/" is used as a path separator in URLs. If you always use "/" as a directory separator, Qt will translate your paths to conform to the underlying operating system.

A QDir can point to a file using either a relative or an absolute path. Absolute paths begin with the directory separator (optionally preceded by a drive specification under Windows). Relative file names begin with a directory name or a file name and specify a path relative to the current directory.

Examples of absolute paths:

  1. QDir("/home/user/Documents")
  2. QDir("C:/Documents and Settings")

On Windows, the second example above will be translated to C:\Documents and Settings when used to access files.

Examples of relative paths:

  1. QDir("images/landscape.png")

You can use the isRelative() or isAbsolute() functions to check if a QDir is using a relative or an absolute file path. Call makeAbsolute() to convert a relative QDir to an absolute one.

Navigation and Directory Operations

A directory's path can be obtained with the path() function, and a new path set with the setPath() function. The absolute path to a directory is found by calling absolutePath().

The name of a directory is found using the dirName() function. This typically returns the last element in the absolute path that specifies the location of the directory. However, it can also return "." if the QDir represents the current directory.

  1. QDir("Documents/Letters/Applications").dirName() // "Applications"
  2. QDir().dirName()                                 // "."

The path for a directory can also be changed with the cd() and cdUp() functions, both of which operate like familiar shell commands. When cd() is called with the name of an existing directory, the QDir object changes directory so that it represents that directory instead. The cdUp() function changes the directory of the QDir object so that it refers to its parent directory; i.e. cd("..") is equivalent to cdUp().

Directories can be created with mkdir(), renamed with rename(), and removed with rmdir().

You can test for the presence of a directory with a given name by using exists(), and the properties of a directory can be tested with isReadable(), isAbsolute(), isRelative(), and isRoot().

The refresh() function re-reads the directory's data from disk.

Files and Directory Contents

Directories contain a number of entries, representing files, directories, and symbolic links. The number of entries in a directory is returned by count(). A string list of the names of all the entries in a directory can be obtained with entryList(). If you need information about each entry, use entryInfoList() to obtain a list of QFileInfo objects.

Paths to files and directories within a directory can be constructed using filePath() and absoluteFilePath(). The filePath() function returns a path to the specified file or directory relative to the path of the QDir object; absoluteFilePath() returns an absolute path to the specified file or directory. Neither of these functions checks for the existence of files or directory; they only construct paths.

  1. QDir directory("Documents/Letters");
  2. QString path = directory.filePath("contents.txt");
  3. QString absolutePath = directory.absoluteFilePath("contents.txt");

Files can be removed by using the remove() function. Directories cannot be removed in the same way as files; use rmdir() to remove them instead.

It is possible to reduce the number of entries returned by entryList() and entryInfoList() by applying filters to a QDir object. You can apply a name filter to specify a pattern with wildcards that file names need to match, an attribute filter that selects properties of entries and can distinguish between files and directories, and a sort order.

Name filters are lists of strings that are passed to setNameFilters(). Attribute filters consist of a bitwise OR combination of Filters, and these are specified when calling setFilter(). The sort order is specified using setSorting() with a bitwise OR combination of SortFlags.

You can test to see if a filename matches a filter using the match() function.

Filter and sort order flags may also be specified when calling entryList() and entryInfoList() in order to override previously defined behavior.

The Current Directory and Other Special Paths

Access to some common directories is provided with a number of static functions that return QDir objects. There are also corresponding functions for these that return strings:

QDir QStringReturn Value
current() currentPath()The application's working directory
home() homePath()The user's home directory
root() rootPath()The root directory
temp() tempPath()The system's temporary directory

The setCurrent() static function can also be used to set the application's working directory.

If you want to find the directory containing the application's executable, see QCoreApplication::applicationDirPath().

The drives() static function provides a list of root directories for each device that contains a filing system. On Unix systems this returns a list containing a single root directory "/"; on Windows the list will usually contain C:/, and possibly other drive letters such as D:/, depending on the configuration of the user's system.

Path Manipulation and Strings

Paths containing "." elements that reference the current directory at that point in the path, ".." elements that reference the parent directory, and symbolic links can be reduced to a canonical form using the canonicalPath() function.

Paths can also be simplified by using cleanPath() to remove redundant "/" and ".." elements.

It is sometimes necessary to be able to show a path in the native representation for the user's platform. The static toNativeSeparators() function returns a copy of the specified path in which each directory separator is replaced by the appropriate separator for the underlying operating system.

Examples

Check if a directory exists:

  1. QDir dir("example");
  2. if (!dir.exists())
  3.     qWarning("Cannot find the example directory");

(We could also use the static convenience function QFile::exists().)

Traversing directories and reading a file:

  1. QDir dir = QDir::root();                 // "/"
  2. if (!dir.cd("tmp"))  {                    // "/tmp"
  3.     qWarning("Cannot find the \"/tmp\" directory");
  4. } else  {
  5.     QFile file(dir.filePath("ex1.txt")); // "/tmp/ex1.txt"
  6.     if (!file.open(QIODevice::ReadWrite))
  7.         qWarning("Cannot create the file %s", file.name());
  8. }

A program that lists all the files in the current directory (excluding symbolic links), sorted by size, smallest first:

  1. #include <QDir>
  2. #include <iostream>
  3.  
  4. int main(int argc, char *argv[])
  5.  {
  6.     QCoreApplication app(argc, argv);
  7.     QDir dir;
  8.     dir.setFilter(QDir::Files | QDir::Hidden | QDir::NoSymLinks);
  9.     dir.setSorting(QDir::Size | QDir::Reversed);
  10.  
  11.     QFileInfoList list = dir.entryInfoList();
  12.     std::cout << "     Bytes Filename" << std::endl;
  13.     for (int i = 0; i < list.size(); ++i)  {
  14.         QFileInfo fileInfo = list.at(i);
  15.         std::cout << qPrintable(QString("%1 %2").arg(fileInfo.size(), 10)
  16.                                                 .arg(fileInfo.fileName()));
  17.         std::cout << std::endl;
  18.     }
  19.     return 0;
  20. }

See also QFileInfo, QFile, QFileDialog, QApplication::applicationDirPath(), and Find Files Example.

Public Types

Toggle detailsenum QDir::

FilterFilter { Dirs , Files , Drives , NoSymLinks , AllEntries Dirs | Files | , TypeMask , All , Readable , Writable , Executable , PermissionMask , RWEMask , Modified , Hidden , System , AccessMask , AllDirs , CaseSensitive , NoDotAndDotDot , NoDot , NoDotDot , NoFilter , DefaultFilter NoFilter ...} { Dirs , Files , Drives , NoSymLinks , AllEntries Dirs | Files | , TypeMask , All , Readable , Writable , Executable , PermissionMask , RWEMask , Modified , Hidden , System , AccessMask , AllDirs , CaseSensitive , NoDotAndDotDot , NoDot , NoDotDot , NoFilter , DefaultFilter NoFilter }

This enum describes the filtering options available to QDir; e.g. for entryList() and entryInfoList(). The filter value is specified by combining values from the following list using the bitwise OR operator:

ConstantValueDescription
QDir::Dirs 0x001 List directories that match the filters.
QDir::AllDirs 0x400 List all directories; i.e. don't apply the filters to directory names.
QDir::Files 0x002 List files.
QDir::Drives 0x004 List disk drives (ignored under Unix).
QDir::NoSymLinks 0x008 Do not list symbolic links (ignored by operating systems that don't support symbolic links).
QDir::NoDotAndDotDot 0x1000 Do not list the special entries "." and "..".
QDir::NoDot 0x2000 Do not list the special entry ".".
QDir::NoDotDot 0x4000 Do not list the special entry "..".
QDir::AllEntries Dirs | Files | Drives List directories, files, drives and symlinks (this does not list broken symlinks unless you specify System).
QDir::Readable 0x010 List files for which the application has read access. The Readable value needs to be combined with Dirs or Files.
QDir::Writable 0x020 List files for which the application has write access. The Writable value needs to be combined with Dirs or Files.
QDir::Executable 0x040 List files for which the application has execute access. The Executable value needs to be combined with Dirs or Files.
QDir::Modified 0x080 Only list files that have been modified (ignored on Unix).
QDir::Hidden 0x100 List hidden files (on Unix, files starting with a ".").
QDir::System 0x200 List system files (on Unix, FIFOs, sockets and device files are included; on Windows, .lnk files are included)
QDir::CaseSensitive 0x800 The filter should be case sensitive.

Functions that use Filter enum values to filter lists of files and directories will include symbolic links to files and directories unless you set the NoSymLinks value.

A default constructed QDir will not filter out files based on their permissions, so entryList() and entryInfoList() will return all files that are readable, writable, executable, or any combination of the three. This makes the default easy to write, and at the same time useful.

For example, setting the Readable, Writable, and Files flags allows all files to be listed for which the application has read access, write access or both. If the Dirs and Drives flags are also included in this combination then all drives, directories, all files that the application can read, write, or execute, and symlinks to such files/directories can be listed.

To retrieve the permissons for a directory, use the entryInfoList() function to get the associated QFileInfo objects and then use the QFileInfo::permissons() to obtain the permissions and ownership for each file.

Look up this member in the source code.

Toggle detailsenum QDir::

SortFlagSortFlag { Name , Time , Size , Unsorted , SortByMask , DirsFirst , Reversed , IgnoreCase , DirsLast , LocaleAware , Type , NoSort , DefaultSort NoSort ...} { Name , Time , Size , Unsorted , SortByMask , DirsFirst , Reversed , IgnoreCase , DirsLast , LocaleAware , Type , NoSort , DefaultSort NoSort }

This enum describes the sort options available to QDir, e.g. for entryList() and entryInfoList(). The sort value is specified by OR-ing together values from the following list:

ConstantValueDescription
QDir::Name 0x00 Sort by name.
QDir::Time 0x01 Sort by time (modification time).
QDir::Size 0x02 Sort by file size.
QDir::Type 0x80 Sort by file type (extension).
QDir::Unsorted 0x03 Do not sort.
QDir::NoSort -1 Not sorted by default.
QDir::DirsFirst 0x04 Put the directories first, then the files.
QDir::DirsLast 0x20 Put the files first, then the directories.
QDir::Reversed 0x08 Reverse the sort order.
QDir::IgnoreCase 0x10 Sort case-insensitively.
QDir::LocaleAware 0x40 Sort items appropriately using the current locale settings.

You can only specify one of the first four.

If you specify both DirsFirst and Reversed, directories are still put first, but in reverse order; the files will be listed after the directories, again in reverse order.

Look up this member in the source code.

    Types

    Toggle detailstypedef QDir FilterSpecFilterSpec

    Use QDir::Filters instead.

    Look up this member in the source code.

    Toggle detailstypedef QDir SortSpecSortSpec

    Use QDir::SortFlags instead.

    Look up this member in the source code.

      Public Functions

      Toggle details QDir

      QDirQDir ( const QDir &dir ) ( const QDir &dir )

      Constructs a QDir object that is a copy of the QDir object for directory dir.

      See also operator=().

      Look up this member in the source code.

      Toggle details QDir

      QDirQDir ( const QString &path=QString() ) ( const QString &path=QString() )

      Constructs a QDir pointing to the given directory path. If path is empty the program's working directory, ("."), is used.

      See also currentPath().

      Look up this member in the source code.

      Toggle details QDir

      QDirQDir ( const QString &path , const QString &nameFilter , SortFlags sort=SortFlags( Name | IgnoreCase ) , Filters filters=AllEntries ...) ( const QString &path , const QString &nameFilter , SortFlags sort=SortFlags( Name | IgnoreCase ) , Filters filters=AllEntries )

      Constructs a QDir with path path, that filters its entries by name using nameFilter and by attributes using filters. It also sorts the names using sort.

      The default nameFilter is an empty string, which excludes nothing; the default filters is AllEntries, which also means exclude nothing. The default sort is Name | IgnoreCase, i.e. sort by name case-insensitively.

      If path is an empty string, QDir uses "." (the current directory). If nameFilter is an empty string, QDir uses the name filter "*" (all files).

      Note that path need not exist.

      See also exists(), setPath(), setNameFilter(), setFilter(), and setSorting().

      Look up this member in the source code.

      Toggle details QDir

      ~QDir~QDir () ()

      Destroys the QDir object frees up its resources. This has no effect on the underlying directory in the file system.

      Look up this member in the source code.

      Toggle details QString QDir

      absoluteFilePathabsoluteFilePath ( const QString &fileName ) ( const QString &fileName )const

      Returns the absolute path name of a file in the directory. Does not check if the file actually exists in the directory; but see exists(). Redundant multiple separators or "." and ".." directories in fileName are not removed (see cleanPath()).

      See also relativeFilePath(), filePath(), and canonicalPath().

      Look up this member in the source code.

      Toggle details QString QDir

      absolutePathabsolutePath () ()const

      Returns the absolute path (a path that starts with "/" or with a drive specification), which may contain symbolic links, but never contains redundant ".", ".." or multiple separators.

      See also setPath(), canonicalPath(), exists(), cleanPath(), dirName(), and absoluteFilePath().

      Look up this member in the source code.

      Toggle details void QDir

      addSearchPathaddSearchPath ( const QString &prefix , const QString &path ...) ( const QString &prefix , const QString &path ) [static]

      Adds path to the search path for prefix.

      See also setSearchPaths().

      Look up this member in the source code.

      Toggle details QString QDir

      canonicalPathcanonicalPath () ()const

      Returns the canonical path, i.e. a path without symbolic links or redundant "." or ".." elements.

      On systems that do not have symbolic links this function will always return the same string that absolutePath() returns. If the canonical path does not exist (normally due to dangling symbolic links) canonicalPath() returns an empty string.

      Example:

      1.                     QString bin = "/local/bin";         // where /local/bin is a symlink to /usr/bin
      2. QDir binDir(bin);
      3. QString canonicalBin = binDir.canonicalPath();
      4. // canonicalBin now equals "/usr/bin"
      5.  
      6. QString ls = "/local/bin/ls";       // where ls is the executable "ls"
      7. QDir lsDir(ls);
      8. QString canonicalLs = lsDir.canonicalPath();
      9. // canonicalLS now equals "/usr/bin/ls".

      See also path(), absolutePath(), exists(), cleanPath(), dirName(), and absoluteFilePath().

      Look up this member in the source code.

      Toggle details bool QDir

      cdcd ( const QString &dirName ) ( const QString &dirName )

      Changes the QDir's directory to dirName.

      Returns true if the new directory exists and is readable; otherwise returns false. Note that the logical cd() operation is not performed if the new directory does not exist.

      Calling cd("..") is equivalent to calling cdUp().

      See also cdUp(), isReadable(), exists(), and path().

      Look up this member in the source code.

      Toggle details bool QDir

      cdUpcdUp () ()

      Changes directory by moving one directory up from the QDir's current directory.

      Returns true if the new directory exists and is readable; otherwise returns false. Note that the logical cdUp() operation is not performed if the new directory does not exist.

      See also cd(), isReadable(), exists(), and path().

      Look up this member in the source code.

      Toggle details QString QDir

      cleanPathcleanPath ( const QString &path ) ( const QString &path ) [static]

      Removes all multiple directory separators "/" and resolves any "."s or ".."s found in the path, path.

      Symbolic links are kept. This function does not return the canonical path, but rather the simplest version of the input. For example, "./local" becomes "local", "local/../bin" becomes "bin" and "/local/usr/../bin" becomes "/local/bin".

      See also absolutePath() and canonicalPath().

      Look up this member in the source code.

      Toggle details uint QDir

      countcount () ()const

      Returns the total number of directories and files in the directory.

      Equivalent to entryList().count().

      See also operator[]() and entryList().

      Look up this member in the source code.

      Toggle details QDir QDir

      currentcurrent () () [static]

      Returns the application's current directory.

      The directory is constructed using the absolute path of the current directory, ensuring that its path() will be the same as its absolutePath().

      See also currentPath(), setCurrent(), home(), root(), and temp().

      Look up this member in the source code.

      Toggle details QString QDir

      currentPathcurrentPath () () [static]

      Returns the absolute path of the application's current directory.

      See also current(), setCurrent(), homePath(), rootPath(), and tempPath().

      Look up this member in the source code.

      Toggle details QString QDir

      dirNamedirName () ()const

      Returns the name of the directory; this is not the same as the path, e.g. a directory with the name "mail", might have the path "/var/spool/mail". If the directory has no name (e.g. it is the root directory) an empty string is returned.

      No check is made to ensure that a directory with this name actually exists; but see exists().

      See also path(), filePath(), absolutePath(), and absoluteFilePath().

      Look up this member in the source code.

      Toggle details QFileInfoList QDir

      drivesdrives () () [static]

      Returns a list of the root directories on this system.

      On Windows this returns a list of QFileInfo objects containing "C:/", "D:/", etc. On other operating systems, it returns a list containing just one root directory (i.e. "/").

      See also root() and rootPath().

      Look up this member in the source code.

      Toggle details QFileInfoList QDir

      entryInfoListentryInfoList ( const QStringList &nameFilters , Filters filters=NoFilter , SortFlags sort=NoSort ...) ( const QStringList &nameFilters , Filters filters=NoFilter , SortFlags sort=NoSort )const

      Returns a list of QFileInfo objects for all the files and directories in the directory, ordered according to the name and attribute filters previously set with setNameFilters() and setFilter(), and sorted according to the flags set with setSorting().

      The name filter, file attribute filter, and sorting specification can be overridden using the nameFilters, filters, and sort arguments.

      Returns an empty list if the directory is unreadable, does not exist, or if nothing matches the specification.

      See also entryList(), setNameFilters(), setSorting(), setFilter(), isReadable(), and exists().

      Look up this member in the source code.

      Toggle details QFileInfoList QDir

      entryInfoListentryInfoList ( Filters filters=NoFilter , SortFlags sort=NoSort ...) ( Filters filters=NoFilter , SortFlags sort=NoSort )const

      This is an overloaded function.

      Returns a list of QFileInfo objects for all the files and directories in the directory, ordered according to the name and attribute filters previously set with setNameFilters() and setFilter(), and sorted according to the flags set with setSorting().

      The attribute filter and sorting specifications can be overridden using the filters and sort arguments.

      Returns an empty list if the directory is unreadable, does not exist, or if nothing matches the specification.

      See also entryList(), setNameFilters(), setSorting(), setFilter(), isReadable(), and exists().

      Look up this member in the source code.

      Toggle details QStringList QDir

      entryListentryList ( const QStringList &nameFilters , Filters filters=NoFilter , SortFlags sort=NoSort ...) ( const QStringList &nameFilters , Filters filters=NoFilter , SortFlags sort=NoSort )const

      Returns a list of the names of all the files and directories in the directory, ordered according to the name and attribute filters previously set with setNameFilters() and setFilter(), and sorted according to the flags set with setSorting().

      The name filter, file attribute filter, and sorting specification can be overridden using the nameFilters, filters, and sort arguments.

      Returns an empty list if the directory is unreadable, does not exist, or if nothing matches the specification.

      See also entryInfoList(), setNameFilters(), setSorting(), and setFilter().

      Look up this member in the source code.

      Toggle details QStringList QDir

      entryListentryList ( Filters filters=NoFilter , SortFlags sort=NoSort ...) ( Filters filters=NoFilter , SortFlags sort=NoSort )const

      This is an overloaded function.

      Returns a list of the names of all the files and directories in the directory, ordered according to the name and attribute filters previously set with setNameFilters() and setFilter(), and sorted according to the flags set with setSorting().

      The attribute filter and sorting specifications can be overridden using the filters and sort arguments.

      Returns an empty list if the directory is unreadable, does not exist, or if nothing matches the specification.

      Note: To list symlinks that point to non existing files, System must be passed to the filter.

      See also entryInfoList(), setNameFilters(), setSorting(), and setFilter().

      Look up this member in the source code.

      Toggle details bool QDir

      existsexists ( const QString &name ) ( const QString &name )const

      Returns true if the file called name exists; otherwise returns false.

      Unless name contains an absolute file path, the file name is assumed to be relative to the directory itself, so this function is typically used to check for the presence of files within a directory.

      See also QFileInfo::exists() and QFile::exists().

      Look up this member in the source code.

      Toggle details bool QDir

      existsexists () ()const

      This is an overloaded function.

      Returns true if the directory exists; otherwise returns false. (If a file with the same name is found this function will return false).

      The overload of this function that accepts an argument is used to test for the presence of files and directories within a directory.

      See also QFileInfo::exists() and QFile::exists().

      Look up this member in the source code.

      Toggle details QString QDir

      filePathfilePath ( const QString &fileName ) ( const QString &fileName )const

      Returns the path name of a file in the directory. Does not check if the file actually exists in the directory; but see exists(). If the QDir is relative the returned path name will also be relative. Redundant multiple separators or "." and ".." directories in fileName are not removed (see cleanPath()).

      See also dirName(), absoluteFilePath(), isRelative(), and canonicalPath().

      Look up this member in the source code.

      Toggle details Filters QDir

      filterfilter () ()const

      Returns the value set by setFilter()

      See also setFilter().

      Look up this member in the source code.

      Toggle details QString QDir

      fromNativeSeparatorsfromNativeSeparators ( const QString &pathName ...) ( const QString &pathName ) [static]

      Returns pathName using '/' as file separator. On Windows, for instance, fromNativeSeparators("c:\\winnt\\system32") returns "c:/winnt/system32".

      The returned string may be the same as the argument on some operating systems, for example on Unix.

      See also toNativeSeparators() and separator().

      Look up this member in the source code.

      Toggle details QDir QDir

      homehome () () [static]

      Returns the user's home directory.

      The directory is constructed using the absolute path of the home directory, ensuring that its path() will be the same as its absolutePath().

      See homePath() for details.

      See also drives(), current(), root(), and temp().

      Look up this member in the source code.

      Toggle details QString QDir

      homePathhomePath () () [static]

      Returns the absolute path of the user's home directory.

      Under Windows this function will return the directory of the current user's profile. Typically, this is:

      1. C:/Documents and Settings/Username

      Use the toNativeSeparators() function to convert the separators to the ones that are appropriate for the underlying operating system.

      If the directory of the current user's profile does not exist or cannot be retrieved, the following alternatives will be checked (in the given order) until an existing and available path is found:

      1. The path specified by the USERPROFILE environment variable.
      2. The path formed by concatenating the HOMEDRIVE and HOMEPATH environment variables.
      3. The path specified by the HOME environment variable.
      4. The path returned by the rootPath() function (which uses the SystemDrive environment variable)
      5. The C:/ directory.

      Under non-Windows operating systems the HOME environment variable is used if it exists, otherwise the path returned by the rootPath(). On Symbian always the same as the path returned by the rootPath().

      See also home(), currentPath(), rootPath(), and tempPath().

      Look up this member in the source code.

      Toggle details bool QDir

      isAbsoluteisAbsolute () ()const

      Returns true if the directory's path is absolute; otherwise returns false. See isAbsolutePath().

      See also isRelative(), makeAbsolute(), and cleanPath().

      Look up this member in the source code.

      Toggle details bool QDir

      isAbsolutePathisAbsolutePath ( const QString &path ) ( const QString &path ) [static]

      Returns true if path is absolute; returns false if it is relative.

      See also isAbsolute(), isRelativePath(), makeAbsolute(), and cleanPath().

      Look up this member in the source code.

      Toggle details bool QDir

      isReadableisReadable () ()const

      Returns true if the directory is readable and we can open files by name; otherwise returns false.

      Warning: A false value from this function is not a guarantee that files in the directory are not accessible.

      See also QFileInfo::isReadable().

      Look up this member in the source code.

      Toggle details bool QDir

      isRelativeisRelative () ()const

      Returns true if the directory path is relative; otherwise returns false. (Under Unix a path is relative if it does not start with a "/").

      See also makeAbsolute(), isAbsolute(), isAbsolutePath(), and cleanPath().

      Look up this member in the source code.

      Toggle details bool QDir

      isRelativePathisRelativePath ( const QString &path ) ( const QString &path ) [static]

      Returns true if path is relative; returns false if it is absolute.

      See also isRelative(), isAbsolutePath(), and makeAbsolute().

      Look up this member in the source code.

      Toggle details bool QDir

      isRootisRoot () ()const

      Returns true if the directory is the root directory; otherwise returns false.

      Note: If the directory is a symbolic link to the root directory this function returns false. If you want to test for this use canonicalPath(), e.g.

      1.                     QDir dir("/tmp/root_link");
      2. dir = dir.canonicalPath();
      3. if (dir.isRoot())
      4.     qWarning("It is a root link");

      See also root() and rootPath().

      Look up this member in the source code.

      Toggle details bool QDir

      makeAbsolutemakeAbsolute () ()

      Converts the directory path to an absolute path. If it is already absolute nothing happens. Returns true if the conversion succeeded; otherwise returns false.

      See also isAbsolute(), isAbsolutePath(), isRelative(), and cleanPath().

      Look up this member in the source code.

      Toggle details bool QDir

      matchmatch ( const QString &filter , const QString &fileName ...) ( const QString &filter , const QString &fileName ) [static]

      Returns true if the fileName matches the wildcard (glob) pattern filter; otherwise returns false. The filter may contain multiple patterns separated by spaces or semicolons. The matching is case insensitive.

      See also QRegExp wildcard matching, QRegExp::exactMatch(), entryList(), and entryInfoList().

      Look up this member in the source code.

      Toggle details bool QDir

      matchmatch ( const QStringList &filters , const QString &fileName ...) ( const QStringList &filters , const QString &fileName ) [static]

      This is an overloaded function.

      Returns true if the fileName matches any of the wildcard (glob) patterns in the list of filters; otherwise returns false. The matching is case insensitive.

      See also QRegExp wildcard matching, QRegExp::exactMatch(), entryList(), and entryInfoList().

      Look up this member in the source code.

      Toggle details bool QDir

      mkdirmkdir ( const QString &dirName ) ( const QString &dirName )const

      Creates a sub-directory called dirName.

      Returns true on success; otherwise returns false.

      See also rmdir().

      Look up this member in the source code.

      Toggle details bool QDir

      mkpathmkpath ( const QString &dirPath ) ( const QString &dirPath )const

      Creates the directory path dirPath.

      The function will create all parent directories necessary to create the directory.

      Returns true if successful; otherwise returns false.

      See also rmpath().

      Look up this member in the source code.

      Toggle details QStringList QDir

      nameFiltersnameFilters () ()const

      Returns the string list set by setNameFilters()

      See also setNameFilters().

      Look up this member in the source code.

      Toggle details QString QDir

      pathpath () ()const

      Returns the path. This may contain symbolic links, but never contains redundant ".", ".." or multiple separators.

      The returned path can be either absolute or relative (see setPath()).

      See also setPath(), absolutePath(), exists(), cleanPath(), dirName(), absoluteFilePath(), toNativeSeparators(), and makeAbsolute().

      Look up this member in the source code.

      Toggle details void QDir

      refreshrefresh () ()const

      Refreshes the directory information.

      Look up this member in the source code.

      Toggle details QString QDir

      relativeFilePathrelativeFilePath ( const QString &fileName ) ( const QString &fileName )const

      Returns the path to fileName relative to the directory.

      1.                     QDir dir("/home/bob");
      2.  
      3. s = dir.relativeFilePath("images/file.jpg");     // s is "images/file.jpg"
      4. s = dir.relativeFilePath("/home/mary/file.txt"); // s is "../mary/file.txt"

      See also absoluteFilePath(), filePath(), and canonicalPath().

      Look up this member in the source code.

      Toggle details bool QDir

      removeremove ( const QString &fileName ) ( const QString &fileName )

      Removes the file, fileName.

      Returns true if the file is removed successfully; otherwise returns false.

      Look up this member in the source code.

      Toggle details bool QDir

      renamerename ( const QString &oldName , const QString &newName ...) ( const QString &oldName , const QString &newName )

      Renames a file or directory from oldName to newName, and returns true if successful; otherwise returns false.

      On most file systems, rename() fails only if oldName does not exist, if newName and oldName are not on the same partition or if a file with the new name already exists. However, there are also other reasons why rename() can fail. For example, on at least one file system rename() fails if newName points to an open file.

      Look up this member in the source code.

      Toggle details bool QDir

      rmdirrmdir ( const QString &dirName ) ( const QString &dirName )const

      Removes the directory specified by dirName.

      The directory must be empty for rmdir() to succeed.

      Returns true if successful; otherwise returns false.

      See also mkdir().

      Look up this member in the source code.

      Toggle details bool QDir

      rmpathrmpath ( const QString &dirPath ) ( const QString &dirPath )const

      Removes the directory path dirPath.

      The function will remove all parent directories in dirPath, provided that they are empty. This is the opposite of mkpath(dirPath).

      Returns true if successful; otherwise returns false.

      See also mkpath().

      Look up this member in the source code.

      Toggle details QDir QDir

      rootroot () () [static]

      Returns the root directory.

      The directory is constructed using the absolute path of the root directory, ensuring that its path() will be the same as its absolutePath().

      See rootPath() for details.

      See also drives(), current(), home(), and temp().

      Look up this member in the source code.

      Toggle details QString QDir

      rootPathrootPath () () [static]

      Returns the absolute path of the root directory.

      For Unix operating systems this returns "/". For Windows file systems this normally returns "c:/". On Symbian this typically returns "c:/data", i.e. the same as native PathInfo::PhoneMemoryRootPath().

      See also root(), drives(), currentPath(), homePath(), and tempPath().

      Look up this member in the source code.

      Toggle details QStringList QDir

      searchPathssearchPaths ( const QString &prefix ) ( const QString &prefix ) [static]

      Returns the search paths for prefix.

      See also setSearchPaths() and addSearchPath().

      Look up this member in the source code.

      Toggle details QChar QDir

      separatorseparator () () [static]

      Returns the native directory separator: "/" under Unix (including Mac OS X) and "\" under Windows.

      You do not need to use this function to build file paths. If you always use "/", Qt will translate your paths to conform to the underlying operating system. If you want to display paths to the user using their operating system's separator use toNativeSeparators().

      Look up this member in the source code.

      Toggle details bool QDir

      setCurrentsetCurrent ( const QString &path ) ( const QString &path ) [static]

      Sets the application's current working directory to path. Returns true if the directory was successfully changed; otherwise returns false.

      See also current(), currentPath(), home(), root(), and temp().

      Look up this member in the source code.

      Toggle details void QDir

      setFiltersetFilter ( Filters filters ) ( Filters filters )

      Sets the filter used by entryList() and entryInfoList() to filters. The filter is used to specify the kind of files that should be returned by entryList() and entryInfoList(). See QDir::Filter.

      See also filter() and setNameFilters().

      Look up this member in the source code.

      Toggle details void QDir

      setNameFilterssetNameFilters ( const QStringList &nameFilters ...) ( const QStringList &nameFilters )

      Sets the name filters used by entryList() and entryInfoList() to the list of filters specified by nameFilters.

      Each name filter is a wildcard (globbing) filter that understands * and ? wildcards. (See QRegExp wildcard matching.)

      For example, the following code sets three name filters on a QDir to ensure that only files with extensions typically used for C++ source files are listed:

      1.     QStringList filters;
      2.     filters << "*.cpp" << "*.cxx" << "*.cc";
      3.     dir.setNameFilters(filters);

      See also nameFilters() and setFilter().

      Look up this member in the source code.

      Toggle details void QDir

      setPathsetPath ( const QString &path ) ( const QString &path )

      Sets the path of the directory to path. The path is cleaned of redundant ".", ".." and of multiple separators. No check is made to see whether a directory with this path actually exists; but you can check for yourself using exists().

      The path can be either absolute or relative. Absolute paths begin with the directory separator "/" (optionally preceded by a drive specification under Windows). Relative file names begin with a directory name or a file name and specify a path relative to the current directory. An example of an absolute path is the string "/tmp/quartz", a relative path might look like "src/fatlib".

      See also path(), absolutePath(), exists(), cleanPath(), dirName(), absoluteFilePath(), isRelative(), and makeAbsolute().

      Look up this member in the source code.

      Toggle details void QDir

      setSearchPathssetSearchPaths ( const QString &prefix , const QStringList &searchPaths ...) ( const QString &prefix , const QStringList &searchPaths ) [static]

      Sets or replaces Qt's search paths for file names with the prefix prefix to searchPaths.

      To specify a prefix for a file name, prepend the prefix followed by a single colon (e.g., "images:undo.png", "xmldocs:books.xml"). prefix can only contain letters or numbers (e.g., it cannot contain a colon, nor a slash).

      Qt uses this search path to locate files with a known prefix. The search path entries are tested in order, starting with the first entry.

      1.                     QDir::setSearchPaths("icons", QStringList(QDir::homePath() + "/images"));
      2. QDir::setSearchPaths("docs", QStringList(":/embeddedDocuments"));
      3. ...
      4. QPixmap pixmap("icons:undo.png"); // will look for undo.png in QDir::homePath() + "/images"
      5. QFile file("docs:design.odf"); // will look in the :/embeddedDocuments resource path

      File name prefix must be at least 2 characters long to avoid conflicts with Windows drive letters.

      Search paths may contain paths to The Qt Resource System.

      See also searchPaths().

      Look up this member in the source code.

      Toggle details void QDir

      setSortingsetSorting ( SortFlags sort ) ( SortFlags sort )

      Sets the sort order used by entryList() and entryInfoList().

      The sort is specified by OR-ing values from the enum QDir::SortFlag.

      See also sorting() and SortFlag.

      Look up this member in the source code.

      Toggle details SortFlags QDir

      sortingsorting () ()const

      Returns the value set by setSorting()

      See also setSorting() and SortFlag.

      Look up this member in the source code.

      Toggle details QDir QDir

      temptemp () () [static]

      Returns the system's temporary directory.

      The directory is constructed using the absolute path of the temporary directory, ensuring that its path() will be the same as its absolutePath().

      See tempPath() for details.

      See also drives(), current(), home(), and root().

      Look up this member in the source code.

      Toggle details QString QDir

      tempPathtempPath () () [static]

      Returns the absolute path of the system's temporary directory.

      On Unix/Linux systems this is usually /tmp; on Windows this is usually the path in the TEMP or TMP environment variable. Whether a directory separator is added to the end or not, depends on the operating system.

      See also temp(), currentPath(), homePath(), and rootPath().

      Look up this member in the source code.

      Toggle details QString QDir

      toNativeSeparatorstoNativeSeparators ( const QString &pathName ...) ( const QString &pathName ) [static]

      Returns pathName with the '/' separators converted to separators that are appropriate for the underlying operating system.

      On Windows, toNativeSeparators("c:/winnt/system32") returns "c:\winnt\system32".

      The returned string may be the same as the argument on some operating systems, for example on Unix.

      See also fromNativeSeparators() and separator().

      Look up this member in the source code.

      Toggle details bool QDir

      operator!=operator!= ( const QDir &dir ) ( const QDir &dir )const

      Returns true if directory dir and this directory have different paths or different sort or filter settings; otherwise returns false.

      Example:

      1. // The current directory is "/usr/local"
      2. QDir d1("/usr/local/bin");
      3. d1.setFilter(QDir::Executable);
      4. QDir d2("bin");
      5. if (d1 != d2)
      6.     qDebug("They differ");

      Look up this member in the source code.

      Toggle details QDir & QDir

      operator=operator= ( const QDir &dir ) ( const QDir &dir )

      Makes a copy of the dir object and assigns it to this QDir object.

      Look up this member in the source code.

      Toggle details bool QDir

      operator==operator== ( const QDir &dir ) ( const QDir &dir )const

      Returns true if directory dir and this directory have the same path and their sort and filter settings are the same; otherwise returns false.

      Example:

      1. // The current directory is "/usr/local"
      2. QDir d1("/usr/local/bin");
      3. QDir d2("bin");
      4. if (d1 == d2)
      5.     qDebug("They're the same");

      Look up this member in the source code.

      Toggle details QString QDir

      operator[]operator[] ( int pos ) ( int pos )const

      Returns the file name at position pos in the list of file names. Equivalent to entryList().at(index). pos must be a valid index position in the list (i.e., 0 <= pos < count()).

      See also count() and entryList().

      Look up this member in the source code.

      Toggle details void QDir

      addResourceSearchPathaddResourceSearchPath ( const QString &path ) ( const QString &path ) [static] Obsolete function

      Use QDir::addSearchPath() with a prefix instead.

      Adds path to the search paths searched in to find resources that are not specified with an absolute path. The default search path is to search only in the root (:/).

      See also The Qt Resource System.

      Look up this member in the source code.

      Toggle details QDir & QDir

      operator=operator= ( const QString &path ) ( const QString &path ) Obsolete function

      This is an overloaded function.

      Sets the directory path to the given path.

      Use setPath() instead.

      Look up this member in the source code.

      Toggle details QString QDir

      absFilePathabsFilePath ( const QString &fileName , bool acceptAbsPath=true ...) ( const QString &fileName , bool acceptAbsPath=true )const Qt3-support

      Use absoluteFilePath(fileName) instead.

      The acceptAbsPath parameter is ignored.

      Look up this member in the source code.

      Toggle details QString QDir

      absPathabsPath () ()const Qt3-support

      Use absolutePath() instead.

      Look up this member in the source code.

      Toggle details QString QDir

      cleanDirPathcleanDirPath ( const QString &name ) ( const QString &name ) [static] Qt3-support

      Use cleanPath() instead.

      Look up this member in the source code.

      Toggle details QString QDir

      convertSeparatorsconvertSeparators ( const QString &pathName ( const QString &pathName ) [static] Qt3-support

      Use QDir::toNativeSeparators() instead.

      Look up this member in the source code.

      Toggle details void QDir

      convertToAbsconvertToAbs () () Qt3-support

      Use makeAbsolute() instead.

      Look up this member in the source code.

      Toggle details QString QDir

      currentDirPathcurrentDirPath () () [static] Qt3-support

      Returns the absolute path of the application's current directory.

      Use currentPath() instead.

      See also currentPath() and setCurrent().

      Look up this member in the source code.

      Toggle details QFileInfoList QDir

      entryInfoListentryInfoList ( const QString &nameFilter , Filters filters=NoFilter , SortFlags sort=NoSort ...) ( const QString &nameFilter , Filters filters=NoFilter , SortFlags sort=NoSort )const Qt3-support

      This is an overloaded function.

      Use the overload that takes a name filter string list as first argument instead of a combination of attribute filter flags.

      Look up this member in the source code.

      Toggle details QStringList QDir

      entryListentryList ( const QString &nameFilter , Filters filters=NoFilter , SortFlags sort=NoSort ...) ( const QString &nameFilter , Filters filters=NoFilter , SortFlags sort=NoSort )const Qt3-support

      This is an overloaded function.

      Use the overload that takes a name filter string list as first argument instead of a combination of attribute filter flags.

      Look up this member in the source code.

      Toggle details QString QDir

      homeDirPathhomeDirPath () () [static] Qt3-support

      Returns the absolute path of the user's home directory.

      Use homePath() instead.

      See also homePath().

      Look up this member in the source code.

      Toggle details bool QDir

      matchAllDirsmatchAllDirs () ()const Qt3-support

      Use filter() & AllDirs instead.

      See also setMatchAllDirs().

      Look up this member in the source code.

      Toggle details bool QDir

      mkdirmkdir ( const QString &dirName , bool acceptAbsPath ...) ( const QString &dirName , bool acceptAbsPath )const Qt3-support

      Use mkdir(dirName) instead.

      The acceptAbsPath parameter is ignored.

      Look up this member in the source code.

      Toggle details QString QDir

      nameFilternameFilter () ()const Qt3-support

      Use nameFilters() instead.

      See also setNameFilter().

      Look up this member in the source code.

      Toggle details bool QDir

      rmdirrmdir ( const QString &dirName , bool acceptAbsPath ...) ( const QString &dirName , bool acceptAbsPath )const Qt3-support

      Use rmdir(dirName) instead.

      The acceptAbsPath parameter is ignored.

      Look up this member in the source code.

      Toggle details QString QDir

      rootDirPathrootDirPath () () [static] Qt3-support

      Returns the absolute path of the root directory.

      Use rootPath() instead.

      See also rootPath().

      Look up this member in the source code.

      Toggle details void QDir

      setMatchAllDirssetMatchAllDirs ( bool on ) ( bool on ) Qt3-support

      Use setFilter() instead.

      See also matchAllDirs().

      Look up this member in the source code.

      Toggle details void QDir

      setNameFiltersetNameFilter ( const QString &nameFilter ) ( const QString &nameFilter ) Qt3-support

      Use setNameFilters() instead.

      The nameFilter is a wildcard (globbing) filter that understands "*" and "?" wildcards. (See QRegExp wildcard matching.) You may specify several filter entries, each separated by spaces or by semicolons.

      For example, if you want entryList() and entryInfoList() to list all files ending with either ".cpp" or ".h", you would use either dir.setNameFilters("*.cpp *.h") or dir.setNameFilters("*.cpp;*.h").

      For example, if you have code like

      1. QString filter = "*.cpp *.cxx *.cc";
      2. dir.setNameFilter(filter);

      you can rewrite it as

      1.                     QString filter = "*.cpp *.cxx *.cc";
      2. dir.setNameFilters(filter.split(' '));

      See also nameFilter().

      Look up this member in the source code.

      Macros

      Toggle detailsQ_CLEANUP_RESOURCEQ_CLEANUP_RESOURCE ( name )

      Unloads the resources specified by the .qrc file with the base name name.

      Normally, Qt resources are unloaded automatically when the application terminates, but if the resources are located in a plugin that is being unloaded, call Q_CLEANUP_RESOURCE() to force removal of your resources.

      Note: This macro cannot be used in a namespace. Please see the Q_INIT_RESOURCE documentation for a workaround.

      Example:

      1. Q_CLEANUP_RESOURCE(myapp);

      See also Q_INIT_RESOURCE() and The Qt Resource System.

      Toggle detailsQ_INIT_RESOURCEQ_INIT_RESOURCE ( name )

      Initializes the resources specified by the .qrc file with the specified base name. Normally, Qt resources are loaded automatically at startup. The Q_INIT_RESOURCE() macro is necessary on some platforms for resources stored in a static library.

      For example, if your application's resources are listed in a file called myapp.qrc, you can ensure that the resources are initialized at startup by adding this line to your main() function:

      1. Q_INIT_RESOURCE(myapp);

      If the file name contains characters that cannot be part of a valid C++ function name (such as '-'), they have to be replaced by the underscore character ('_').

      Note: This macro cannot be used in a namespace. It should be called from main(). If that is not possible, the following workaround can be used to init the resource myapp from the function MyNamespace::myFunction:

      1. inline void initMyResource()  { Q_INIT_RESOURCE(myapp); }
      2.  
      3. namespace MyNamespace
      4.  {
      5.     ...
      6.  
      7.     void myFunction()
      8.      {
      9.         initMyResource();
      10.     }
      11. }

      See also Q_CLEANUP_RESOURCE() and The Qt Resource System.

        Notes provided by the Qt Community
        Informative
        • 5

        Votes: 1

        Coverage: Qt library 4.7, 4.8, 5.0

        Picture of Volker Volker

        Ant Farmer
        35 notes

        Nokia Certified Qt Developer

        Q_INIT_RESOURCE: names must be unique

        If you have multiple resources, say from multiple (static) libs, you must make sure that the names of the resource files (filename of the .qrc/.rcc) are unique. Otherwise only one one of the equal named resources is available in your application, but not the others.

        [Revisions]

        Informative
        • 0

        Votes: 0

        Coverage: Qt library 4.7, Qt 4.8

        Picture of Diluka Diluka

        Hobby Entomologist
        23 notes

        QDir available sort options

        1. Constant  |     Value  |        Description
        2. QDir::Name      0x00    Sort by name.
        3. QDir::Time      0x01    Sort by time (modification time).
        4. QDir::Size      0x02    Sort by file size.
        5. QDir::Type      0x80    Sort by file type (extension).
        6. QDir::Unsorted  0x03    Do not sort.
        7. QDir::NoSort    -1      Not sorted by default.
        8. QDir::DirsFirst 0x04    Put the directories first, then the files.
        9. QDir::DirsLast  0x20    Put the files first, then the directories.
        10. QDir::Reversed  0x08    Reverse the sort order.
        11. QDir::IgnoreCase        0x10    Sort case-insensitively.
        12. QDir::LocaleAware       0x40    Sort items appropriately using the current locale settings.

        [Revisions]

        Informative
        • 0

        Votes: 0

        Coverage: Qt library 4.7, Qt 4.8

        Picture of Diluka Diluka

        Hobby Entomologist
        23 notes

        Filtering options available in QDir

        1. Constant  |     Value | Description
        2. QDir::Dirs      0x001   List directories that match the filters.
        3. QDir::AllDirs   0x400   List all directories; i.e. don't apply the filters to directory names.
        4. QDir::Files     0x002   List files.
        5. QDir::Drives    0x004   List disk drives (ignored under Unix).
        6. QDir::NoSymLinks        0x008   Do not list symbolic links (ignored by operating systems that don't support symbolic links).
        7. QDir::NoDotAndDotDot    0x1000  Do not list the special entries "." and "..".
        8. QDir::NoDot     0x2000  Do not list the special entry ".".
        9. QDir::NoDotDot  0x4000  Do not list the special entry "..".
        10. QDir::AllEntries        Dirs | Files | Drives   List directories, files, drives and symlinks (this does not list broken symlinks unless you specify System).
        11. QDir::Readable  0x010   List files for which the application has read access. The Readable value needs to be combined with Dirs or Files.
        12. QDir::Writable  0x020   List files for which the application has write access. The Writable value needs to be combined with Dirs or Files.
        13. QDir::Executable        0x040   List files for which the application has execute access. The Executable value needs to be combined with Dirs or Files.
        14. QDir::Modified  0x080   Only list files that have been modified (ignored on Unix).
        15. QDir::Hidden    0x100   List hidden files (on Unix, files starting with a ".").
        16. QDir::System    0x200   List system files (on Unix, FIFOs, sockets and device files are included; on Windows, .lnk files are included)
        17. QDir::CaseSensitive     0x800   The filter should be case sensitive.

        [Revisions]