src_corelib_text_qbytearray.cpp

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// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
 
 
void wrapInFunction()
{
 
QByteArray ba("Hello");
 
 
QByteArray ba;
ba.resize(5);
ba[0] = 0x3c;
ba[1] = 0xb8;
ba[2] = 0x64;
ba[3] = 0x18;
ba[4] = 0xca;
 
 
for (qsizetype i = 0; i < ba.size(); ++i) {
    if (ba.at(i) >= 'a' && ba.at(i) <= 'f')
        cout << "Found character in range [a-f]" << endl;
}
 
 
QByteArray x("and");
x.prepend("rock ");         // x == "rock and"
x.append(" roll");          // x == "rock and roll"
x.replace(5, 3, "&");       // x == "rock & roll"
 
 
QByteArray ba("We must be <b>bold</b>, very <b>bold</b>");
qsizetype j = 0;
while ((j = ba.indexOf("<b>", j)) != -1) {
    cout << "Found <b> tag at index position " << j << endl;
    ++j;
}
 
 
QByteArray().isNull();          // returns true
QByteArray().isEmpty();         // returns true
 
QByteArray("").isNull();        // returns false
QByteArray("").isEmpty();       // returns true
 
QByteArray("abc").isNull();     // returns false
QByteArray("abc").isEmpty();    // returns false
 
 
QByteArray ba("Hello");
qsizetype n = ba.size();    // n == 5
ba.data()[0];               // returns 'H'
ba.data()[4];               // returns 'o'
ba.data()[5];               // returns '\0'
 
 
QByteArray().isEmpty();         // returns true
QByteArray("").isEmpty();       // returns true
QByteArray("abc").isEmpty();    // returns false
 
 
QByteArray ba("Hello world");
char *data = ba.data();
while (*data) {
    cout << "[" << *data << "]" << endl;
    ++data;
}
 
 
QByteArray ba("Hello, world");
cout << ba[0]; // prints H
ba[7] = 'W';
// ba == "Hello, World"
 
 
QByteArray ba("Stockholm");
ba.truncate(5);             // ba == "Stock"
 
 
QByteArray ba("STARTTLS\r\n");
ba.chop(2);                 // ba == "STARTTLS"
 
 
QByteArray x("free");
QByteArray y("dom");
x += y;
// x == "freedom"
 
 
QByteArray().isNull();          // returns true
QByteArray("").isNull();        // returns false
QByteArray("abc").isNull();     // returns false
 
 
QByteArray ba("Istambul");
ba.fill('o');
// ba == "oooooooo"
 
ba.fill('X', 2);
// ba == "XX"
 
 
QByteArray x("ship");
QByteArray y("air");
x.prepend(y);
// x == "airship"
 
 
QByteArray x("free");
QByteArray y("dom");
x.append(y);
// x == "freedom"
 
 
QByteArray ba("Meal");
ba.insert(1, QByteArrayView("ontr"));
// ba == "Montreal"
 
 
QByteArray ba("Montreal");
ba.remove(1, 4);
// ba == "Meal"
 
 
QByteArray x("Say yes!");
QByteArray y("no");
x.replace(4, 3, y);
// x == "Say no!"
 
 
QByteArray ba("colour behaviour flavour neighbour");
ba.replace(QByteArray("ou"), QByteArray("o"));
// ba == "color behavior flavor neighbor"
 
 
QByteArray x("sticky question");
QByteArrayView y("sti");
x.indexOf(y);               // returns 0
x.indexOf(y, 1);            // returns 10
x.indexOf(y, 10);           // returns 10
x.indexOf(y, 11);           // returns -1
 
 
QByteArray ba("ABCBA");
ba.indexOf("B");            // returns 1
ba.indexOf("B", 1);         // returns 1
ba.indexOf("B", 2);         // returns 3
ba.indexOf("X");            // returns -1
 
 
QByteArray x("crazy azimuths");
QByteArrayView y("az");
x.lastIndexOf(y);           // returns 6
x.lastIndexOf(y, 6);        // returns 6
x.lastIndexOf(y, 5);        // returns 2
x.lastIndexOf(y, 1);        // returns -1
 
 
QByteArray ba("ABCBA");
ba.lastIndexOf("B");        // returns 3
ba.lastIndexOf("B", 3);     // returns 3
ba.lastIndexOf("B", 2);     // returns 1
ba.lastIndexOf("X");        // returns -1
 
 
QByteArray url("ftp://ftp.qt-project.org/");
if (url.startsWith("ftp:"))
    ...
 
 
QByteArray url("http://qt-project.org/doc/qt-5.0/qtdoc/index.html");
if (url.endsWith(".html"))
    ...
 
 
QByteArray x("Pineapple");
QByteArray y = x.first(4);
// y == "Pine"
 
 
QByteArray x("Pineapple");
QByteArray y = x.last(5);
// y == "apple"
 
 
QByteArray x("Five pineapples");
QByteArray y = x.sliced(5, 4);     // y == "pine"
QByteArray z = x.sliced(5);        // z == "pineapples"
 
 
QByteArray x("Qt by THE QT COMPANY");
QByteArray y = x.toLower();
// y == "qt by the qt company"
 
 
QByteArray x("Qt by THE QT COMPANY");
QByteArray y = x.toUpper();
// y == "QT BY THE QT COMPANY"
 
 
QByteArray ba("  lots\t of\nwhitespace\r\n ");
ba = ba.simplified();
// ba == "lots of whitespace";
 
 
QByteArray ba("  lots\t of\nwhitespace\r\n ");
ba = ba.trimmed();
// ba == "lots\t of\nwhitespace";
 
 
QByteArray x("apple");
QByteArray y = x.leftJustified(8, '.');   // y == "apple..."
 
 
QByteArray x("apple");
QByteArray y = x.rightJustified(8, '.');    // y == "...apple"
 
 
QByteArray str("FF");
bool ok;
int hex = str.toInt(&ok, 16);     // hex == 255, ok == true
int dec = str.toInt(&ok, 10);     // dec == 0, ok == false
 
 
QByteArray str("FF");
bool ok;
long hex = str.toLong(&ok, 16);   // hex == 255, ok == true
long dec = str.toLong(&ok, 10);   // dec == 0, ok == false
 
 
QByteArray string("1234.56");
bool ok;
double a = string.toDouble(&ok);   // a == 1234.56, ok == true
 
string = "1234.56 Volt";
a = str.toDouble(&ok);             // a == 0, ok == false
 
QByteArray string("1234.56");
bool ok;
float a = string.toFloat(&ok);    // a == 1234.56, ok == true
 
string = "1234.56 Volt";
a = str.toFloat(&ok);              // a == 0, ok == false
 
QByteArray text("Qt is great!");
text.toBase64();        // returns "UXQgaXMgZ3JlYXQh"
 
QByteArray text("<p>Hello?</p>");
text.toBase64(QByteArray::Base64Encoding | QByteArray::OmitTrailingEquals);      // returns "PHA+SGVsbG8/PC9wPg"
text.toBase64(QByteArray::Base64Encoding);                                       // returns "PHA+SGVsbG8/PC9wPg=="
text.toBase64(QByteArray::Base64UrlEncoding);                                    // returns "PHA-SGVsbG8_PC9wPg=="
text.toBase64(QByteArray::Base64UrlEncoding | QByteArray::OmitTrailingEquals);   // returns "PHA-SGVsbG8_PC9wPg"
 
QByteArray ba;
int n = 63;
ba.setNum(n);           // ba == "63"
ba.setNum(n, 16);       // ba == "3f"
 
 
int n = 63;
QByteArray::number(n);              // returns "63"
QByteArray::number(n, 16);          // returns "3f"
QByteArray::number(n, 16).toUpper();  // returns "3F"
 
 
QByteArray ba = QByteArray::number(12.3456, 'E', 3);
// ba == 1.235E+01
 
 
 static const char mydata[] = {
    '\x00', '\x00', '\x03', '\x84', '\x78', '\x9c', '\x3b', '\x76',
    '\xec', '\x18', '\xc3', '\x31', '\x0a', '\xf1', '\xcc', '\x99',
    ...
    '\x6d', '\x5b'
};
 
QByteArray data = QByteArray::fromRawData(mydata, sizeof(mydata));
QDataStream in(&data, QIODevice::ReadOnly);
...
 
 
QByteArray text = QByteArray::fromBase64("UXQgaXMgZ3JlYXQh");
text.data();            // returns "Qt is great!"
 
QByteArray::fromBase64("PHA+SGVsbG8/PC9wPg==", QByteArray::Base64Encoding); // returns "<p>Hello?</p>"
QByteArray::fromBase64("PHA-SGVsbG8_PC9wPg==", QByteArray::Base64UrlEncoding); // returns "<p>Hello?</p>"
 
void process(const QByteArray &);
 
if (auto result = QByteArray::fromBase64Encoding(encodedData))
    process(*result);
 
auto result = QByteArray::fromBase64Encoding(encodedData);
if (result.decodingStatus == QByteArray::Base64DecodingStatus::Ok)
    process(result.decoded);
 
QByteArray text = QByteArray::fromHex("517420697320677265617421");
text.data();            // returns "Qt is great!"
 
QString tmp = "test";
QByteArray text = tmp.toLocal8Bit();
char *data = new char[text.size()];
strcpy(data, text.data());
delete [] data;
 
QString tmp = "test";
QByteArray text = tmp.toLocal8Bit();
char *data = new char[text.size() + 1];
strcpy(data, text.data());
delete [] data;
 
QByteArray ba1("ca\0r\0t");
ba1.size();                     // Returns 2.
ba1.constData();                // Returns "ca" with terminating \0.
 
QByteArray ba2("ca\0r\0t", 3);
ba2.size();                     // Returns 3.
ba2.constData();                // Returns "ca\0" with terminating \0.
 
QByteArray ba3("ca\0r\0t", 4);
ba3.size();                     // Returns 4.
ba3.constData();                // Returns "ca\0r" with terminating \0.
 
const char cart[] = {'c', 'a', '\0', 'r', '\0', 't'};
QByteArray ba4(QByteArray::fromRawData(cart, 6));
ba4.size();                     // Returns 6.
ba4.constData();                // Returns "ca\0r\0t" without terminating \0.
 
QByteArray ba("ab");
ba.repeated(4);             // returns "abababab"
 
QByteArray macAddress = QByteArray::fromHex("123456abcdef");
macAddress.toHex(':'); // returns "12:34:56:ab:cd:ef"
macAddress.toHex(0);   // returns "123456abcdef"
 
QByteArray text = QByteArray::fromPercentEncoding("Qt%20is%20great%33");
qDebug("%s", text.data());      // reports "Qt is great!"
 
QByteArray text = "{a fishy string?}";
QByteArray ba = text.toPercentEncoding("{}", "s");
qDebug("%s", ba.constData());
// prints "{a fi%73hy %73tring%3F}"
 
QByteArray ba = QByteArrayLiteral("byte array contents");
 
QByteArray encoded("Qt%20is%20great%33");
QByteArray decoded = encoded.percentDecoded(); // Set to "Qt is great!"
 
emscripten::val uint8array = emscripten::val::global("g_uint8array");
QByteArray byteArray = QByteArray::fromEcmaUint8Array(uint8array);
 
QByteArray byteArray = "test";
emscripten::val uint8array = QByteArray::toEcmaUint8Array(byteArray);
 
QByteArray x = "Five pineapples"_ba;
x.slice(5);     // x == "pineapples"
x.slice(4, 3);  // x == "app"
 
}