QNetworkRequest Class Reference

The QNetworkRequest class holds a request to be sent with QNetworkAccessManager.

  1. #include <QNetworkRequest>

This class was introduced in Qt 4.4.

Detailed Description

The QNetworkRequest class holds a request to be sent with QNetworkAccessManager.

QNetworkRequest is part of the Network Access API and is the class holding the information necessary to send a request over the network. It contains a URL and some ancillary information that can be used to modify the request.

See also QNetworkReply and QNetworkAccessManager.

Public Types

Toggle detailsenum QNetworkRequest::

AttributeAttribute { HttpStatusCodeAttribute , HttpReasonPhraseAttribute , RedirectionTargetAttribute , ConnectionEncryptedAttribute , CacheLoadControlAttribute , CacheSaveControlAttribute , SourceIsFromCacheAttribute , DoNotBufferUploadDataAttribute , HttpPipeliningAllowedAttribute , HttpPipeliningWasUsedAttribute , CustomVerbAttribute , CookieLoadControlAttribute , AuthenticationReuseAttribute , CookieSaveControlAttribute , MaximumDownloadBufferSizeAttribute , DownloadBufferAttribute , User , UserMax 32767 ...} { HttpStatusCodeAttribute , HttpReasonPhraseAttribute , RedirectionTargetAttribute , ConnectionEncryptedAttribute , CacheLoadControlAttribute , CacheSaveControlAttribute , SourceIsFromCacheAttribute , DoNotBufferUploadDataAttribute , HttpPipeliningAllowedAttribute , HttpPipeliningWasUsedAttribute , CustomVerbAttribute , CookieLoadControlAttribute , AuthenticationReuseAttribute , CookieSaveControlAttribute , MaximumDownloadBufferSizeAttribute , DownloadBufferAttribute , User , UserMax 32767 }

Attribute codes for the QNetworkRequest and QNetworkReply.

Attributes are extra meta-data that are used to control the behavior of the request and to pass further information from the reply back to the application. Attributes are also extensible, allowing custom implementations to pass custom values.

The following table explains what the default attribute codes are, the QVariant types associated, the default value if said attribute is missing and whether it's used in requests or replies.

ConstantValueDescription
QNetworkRequest::HttpStatusCodeAttribute 0 Replies only, type: QVariant::Int (no default) Indicates the HTTP status code received from the HTTP server (like 200, 304, 404, 401, etc.). If the connection was not HTTP-based, this attribute will not be present.
QNetworkRequest::HttpReasonPhraseAttribute 1 Replies only, type: QVariant::ByteArray (no default) Indicates the HTTP reason phrase as received from the HTTP server (like "Ok", "Found", "Not Found", "Access Denied", etc.) This is the human-readable representation of the status code (see above). If the connection was not HTTP-based, this attribute will not be present.
QNetworkRequest::RedirectionTargetAttribute 2 Replies only, type: QVariant::Url (no default) If present, it indicates that the server is redirecting the request to a different URL. The Network Access API does not by default follow redirections: it's up to the application to determine if the requested redirection should be allowed, according to its security policies. The returned URL might be relative. Use QUrl::resolved() to create an absolute URL out of it.
QNetworkRequest::ConnectionEncryptedAttribute 3 Replies only, type: QVariant::Bool (default: false) Indicates whether the data was obtained through an encrypted (secure) connection.
QNetworkRequest::CacheLoadControlAttribute 4 Requests only, type: QVariant::Int (default: QNetworkRequest::PreferNetwork) Controls how the cache should be accessed. The possible values are those of QNetworkRequest::CacheLoadControl. Note that the default QNetworkAccessManager implementation does not support caching. However, this attribute may be used by certain backends to modify their requests (for example, for caching proxies).
QNetworkRequest::CacheSaveControlAttribute 5 Requests only, type: QVariant::Bool (default: true) Controls if the data obtained should be saved to cache for future uses. If the value is false, the data obtained will not be automatically cached. If true, data may be cached, provided it is cacheable (what is cacheable depends on the protocol being used).
QNetworkRequest::SourceIsFromCacheAttribute 6 Replies only, type: QVariant::Bool (default: false) Indicates whether the data was obtained from cache or not.
QNetworkRequest::DoNotBufferUploadDataAttribute 7 Requests only, type: QVariant::Bool (default: false) Indicates whether the QNetworkAccessManager code is allowed to buffer the upload data, e.g. when doing a HTTP POST. When using this flag with sequential upload data, the ContentLengthHeader header must be set.
QNetworkRequest::HttpPipeliningAllowedAttribute 8 Requests only, type: QVariant::Bool (default: false) Indicates whether the QNetworkAccessManager code is allowed to use HTTP pipelining with this request.
QNetworkRequest::HttpPipeliningWasUsedAttribute 9 Replies only, type: QVariant::Bool Indicates whether the HTTP pipelining was used for receiving this reply.
QNetworkRequest::CustomVerbAttribute 10 Requests only, type: QVariant::ByteArray Holds the value for the custom HTTP verb to send (destined for usage of other verbs than GET, POST, PUT and DELETE). This verb is set when calling QNetworkAccessManager::sendCustomRequest().
QNetworkRequest::CookieLoadControlAttribute 11 Requests only, type: QVariant::Int (default: QNetworkRequest::Automatic) Indicates whether to send 'Cookie' headers in the request. This attribute is set to false by QtWebKit when creating a cross-origin XMLHttpRequest where withCredentials has not been set explicitly to true by the Javascript that created the request. See here for more information. (This value was introduced in 4.7.)
QNetworkRequest::CookieSaveControlAttribute 13 Requests only, type: QVariant::Int (default: QNetworkRequest::Automatic) Indicates whether to save 'Cookie' headers received from the server in reply to the request. This attribute is set to false by QtWebKit when creating a cross-origin XMLHttpRequest where withCredentials has not been set explicitly to true by the Javascript that created the request. See here for more information. (This value was introduced in 4.7.)
QNetworkRequest::AuthenticationReuseAttribute 12 Requests only, type: QVariant::Int (default: QNetworkRequest::Automatic) Indicates whether to use cached authorization credentials in the request, if available. If this is set to QNetworkRequest::Manual and the authentication mechanism is 'Basic' or 'Digest', Qt will not send an an 'Authorization' HTTP header with any cached credentials it may have for the request's URL. This attribute is set to QNetworkRequest::Manual by QtWebKit when creating a cross-origin XMLHttpRequest where withCredentials has not been set explicitly to true by the Javascript that created the request. See here for more information. (This value was introduced in 4.7.)
QNetworkRequest::User 1000 Special type. Additional information can be passed in QVariants with types ranging from User to UserMax. The default implementation of Network Access will ignore any request attributes in this range and it will not produce any attributes in this range in replies. The range is reserved for extensions of QNetworkAccessManager.
QNetworkRequest::UserMax 32767 Special type. See User.

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Toggle detailsenum QNetworkRequest::

CacheLoadControlCacheLoadControl { AlwaysNetwork , PreferNetwork , PreferCache , AlwaysCache 3 ...} { AlwaysNetwork , PreferNetwork , PreferCache , AlwaysCache 3 }

Controls the caching mechanism of QNetworkAccessManager.

ConstantValueDescription
QNetworkRequest::AlwaysNetwork 0 always load from network and do not check if the cache has a valid entry (similar to the "Reload" feature in browsers)
QNetworkRequest::PreferNetwork 1 default value; load from the network if the cached entry is older than the network entry
QNetworkRequest::PreferCache 2 load from cache if available, otherwise load from network. Note that this can return possibly stale (but not expired) items from cache.
QNetworkRequest::AlwaysCache 3 only load from cache, indicating error if the item was not cached (i.e., off-line mode)

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Toggle detailsenum QNetworkRequest::

KnownHeadersKnownHeaders { ContentTypeHeader , ContentLengthHeader , LocationHeader , LastModifiedHeader , CookieHeader , SetCookieHeader 5 ...} { ContentTypeHeader , ContentLengthHeader , LocationHeader , LastModifiedHeader , CookieHeader , SetCookieHeader 5 }

List of known header types that QNetworkRequest parses. Each known header is also represented in raw form with its full HTTP name.

ConstantValueDescription
QNetworkRequest::ContentTypeHeader 0 corresponds to the HTTP Content-Type header and contains a string containing the media (MIME) type and any auxiliary data (for instance, charset)
QNetworkRequest::ContentLengthHeader 1 corresponds to the HTTP Content-Length header and contains the length in bytes of the data transmitted.
QNetworkRequest::LocationHeader 2 corresponds to the HTTP Location header and contains a URL representing the actual location of the data, including the destination URL in case of redirections.
QNetworkRequest::LastModifiedHeader 3 corresponds to the HTTP Last-Modified header and contains a QDateTime representing the last modification date of the contents
QNetworkRequest::CookieHeader 4 corresponds to the HTTP Cookie header and contains a QList<QNetworkCookie> representing the cookies to be sent back to the server
QNetworkRequest::SetCookieHeader 5 corresponds to the HTTP Set-Cookie header and contains a QList<QNetworkCookie> representing the cookies sent by the server to be stored locally

See also header(), setHeader(), rawHeader(), and setRawHeader().

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Toggle detailsenum QNetworkRequest::

LoadControlLoadControl { Automatic , Manual 1 ...} { Automatic , Manual 1 }

Indicates if an aspect of the request's loading mechanism has been manually overridden, e.g. by QtWebKit.

ConstantValueDescription
QNetworkRequest::Automatic 0 default value: indicates default behaviour.
QNetworkRequest::Manual 1 indicates behaviour has been manually overridden.

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Toggle detailsenum QNetworkRequest::

PriorityPriority { HighPriority , NormalPriority , LowPriority 5 ...} { HighPriority , NormalPriority , LowPriority 5 }

This enum lists the possible network request priorities.

ConstantValueDescription
QNetworkRequest::HighPriority 1 High priority
QNetworkRequest::NormalPriority 3 Normal priority
QNetworkRequest::LowPriority 5 Low priority

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    Public Functions

    Toggle details QNetworkRequest

    QNetworkRequestQNetworkRequest ( const QUrl &url=QUrl() ) ( const QUrl &url=QUrl() )

    Constructs a QNetworkRequest object with url as the URL to be requested.

    See also url() and setUrl().

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    Toggle details QNetworkRequest

    QNetworkRequestQNetworkRequest ( const QNetworkRequest &other ) ( const QNetworkRequest &other )

    Creates a copy of other.

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    Toggle details QNetworkRequest

    ~QNetworkRequest~QNetworkRequest () ()

    Disposes of the QNetworkRequest object.

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    Toggle details QVariant QNetworkRequest

    attributeattribute ( Attribute code , const QVariant &defaultValue=QVariant() ...) ( Attribute code , const QVariant &defaultValue=QVariant() )const

    Returns the attribute associated with the code code. If the attribute has not been set, it returns defaultValue.

    Note: this function does not apply the defaults listed in QNetworkRequest::Attribute.

    See also setAttribute() and QNetworkRequest::Attribute.

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    Toggle details bool QNetworkRequest

    hasRawHeaderhasRawHeader ( const QByteArray &headerName ) ( const QByteArray &headerName )const

    Returns true if the raw header headerName is present in this network request.

    See also rawHeader() and setRawHeader().

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    Toggle details QVariant QNetworkRequest

    headerheader ( KnownHeaders header ) ( KnownHeaders header )const

    Returns the value of the known network header header if it is present in this request. If it is not present, returns QVariant() (i.e., an invalid variant).

    See also KnownHeaders, rawHeader(), and setHeader().

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    Toggle details QObject * QNetworkRequest

    originatingObjectoriginatingObject () ()const

    Returns a reference to the object that initiated this network request; returns 0 if not set or the object has been destroyed.

    See also setOriginatingObject().

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    Toggle details Priority QNetworkRequest

    prioritypriority () ()const

    Return the priority of this request.

    See also setPriority().

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    Toggle details QByteArray QNetworkRequest

    rawHeaderrawHeader ( const QByteArray &headerName ( const QByteArray &headerName )const

    Returns the raw form of header headerName. If no such header is present, an empty QByteArray is returned, which may be indistinguishable from a header that is present but has no content (use hasRawHeader() to find out if the header exists or not).

    Raw headers can be set with setRawHeader() or with setHeader().

    See also header() and setRawHeader().

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    Toggle details QList <QByteArray > QNetworkRequest

    rawHeaderListrawHeaderList () ()const

    Returns a list of all raw headers that are set in this network request. The list is in the order that the headers were set.

    See also hasRawHeader() and rawHeader().

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    Toggle details void QNetworkRequest

    setAttributesetAttribute ( Attribute code , const QVariant &value ...) ( Attribute code , const QVariant &value )

    Sets the attribute associated with code code to be value value. If the attribute is already set, the previous value is discarded. In special, if value is an invalid QVariant, the attribute is unset.

    See also attribute() and QNetworkRequest::Attribute.

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    Toggle details void QNetworkRequest

    setHeadersetHeader ( KnownHeaders header , const QVariant &value ...) ( KnownHeaders header , const QVariant &value )

    Sets the value of the known header header to be value, overriding any previously set headers. This operation also sets the equivalent raw HTTP header.

    See also KnownHeaders, setRawHeader(), and header().

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    Toggle details void QNetworkRequest

    setOriginatingObjectsetOriginatingObject ( QObject *object ) ( QObject *object )

    Allows setting a reference to the object initiating the request.

    For example QtWebKit sets the originating object to the QWebFrame that initiated the request.

    See also originatingObject().

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    Toggle details void QNetworkRequest

    setPrioritysetPriority ( Priority priority ) ( Priority priority )

    Set the priority of this request to priority.

    Note: The priority is only a hint to the network access manager. It can use it or not. Currently it is used for HTTP to decide which request should be sent first to a server.

    See also priority().

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    Toggle details void QNetworkRequest

    setRawHeadersetRawHeader ( const QByteArray &headerName , const QByteArray &headerValue ...) ( const QByteArray &headerName , const QByteArray &headerValue )

    Sets the header headerName to be of value headerValue. If headerName corresponds to a known header (see QNetworkRequest::KnownHeaders), the raw format will be parsed and the corresponding "cooked" header will be set as well.

    For example:

    1. request.setRawHeader("Last-Modified", "Sun, 06 Nov 1994 08:49:37 GMT");

    will also set the known header LastModifiedHeader to be the QDateTime object of the parsed date.

    Note: setting the same header twice overrides the previous setting. To accomplish the behaviour of multiple HTTP headers of the same name, you should concatenate the two values, separating them with a comma (",") and set one single raw header.

    See also KnownHeaders, setHeader(), hasRawHeader(), and rawHeader().

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    Toggle details void QNetworkRequest

    setSslConfigurationsetSslConfiguration ( const QSslConfiguration &config ...) ( const QSslConfiguration &config )

    Sets this network request's SSL configuration to be config. The settings that apply are the private key, the local certificate, the SSL protocol (SSLv2, SSLv3, TLSv1 where applicable), the CA certificates and the ciphers that the SSL backend is allowed to use.

    By default, no SSL configuration is set, which allows the backends to choose freely what configuration is best for them.

    See also sslConfiguration() and QSslConfiguration::defaultConfiguration().

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    Toggle details void QNetworkRequest

    setUrlsetUrl ( const QUrl &url ) ( const QUrl &url )

    Sets the URL this network request is referring to to be url.

    See also url().

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    Toggle details QSslConfiguration QNetworkRequest

    sslConfigurationsslConfiguration () ()const

    Returns this network request's SSL configuration. By default, no SSL settings are specified.

    See also setSslConfiguration().

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    Toggle details QUrl QNetworkRequest

    urlurl () ()const

    Returns the URL this network request is referring to.

    See also setUrl().

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    Toggle details bool QNetworkRequest

    operator!=operator!= ( const QNetworkRequest &other ) ( const QNetworkRequest &other )const

    Returns false if this object is not the same as other.

    See also operator==().

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    Toggle details QNetworkRequest & QNetworkRequest

    operator=operator= ( const QNetworkRequest &other ...) ( const QNetworkRequest &other )

    Creates a copy of other

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    Toggle details bool QNetworkRequest

    operator==operator== ( const QNetworkRequest &other ) ( const QNetworkRequest &other )const

    Returns true if this object is the same as other (i.e., if they have the same URL, same headers and same meta-data settings).

    See also operator!=().

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