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
 
#include <QByteArray>
#include <QDataStream>
#include <QIODevice>
#include <iostream>
 
using namespace std;
 
void wrapInFunction()
{
    {
        //! [0]
        QByteArray ba("Hello");
        //! [0]
    }
 
    {
        //! [1]
        QByteArray ba;
        ba.resize(5);
        ba[0] = 0x3c;
        ba[1] = 0xb8;
        ba[2] = 0x64;
        ba[3] = 0x18;
        ba[4] = 0xca;
        //! [1]
    }
 
    {
        QByteArray ba("");
 
        //! [2]
        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;
        }
        //! [2]
    }
 
    {
        //! [3]
        QByteArray x("and");
        x.prepend("rock ");         // x == "rock and"
        x.append(" roll");          // x == "rock and roll"
        x.replace(5, 3, "&");       // x == "rock & roll"
        //! [3]
    }
 
    {
        //! [4]
        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;
        }
        //! [4]
    }
 
    {
        //! [5]
        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
        //! [5]
    }
 
    {
        //! [6]
        QByteArray ba("Hello");
        qsizetype n = ba.size();    // n == 5
        ba.data()[0];               // returns 'H'
        ba.data()[4];               // returns 'o'
        ba.data()[5];               // returns '\0'
        //! [6]
    }
 
    {
        //! [7]
        QByteArray().isEmpty();         // returns true
        QByteArray("").isEmpty();       // returns true
        QByteArray("abc").isEmpty();    // returns false
        //! [7]
    }
 
    {
        //! [8]
        QByteArray ba("Hello world");
        char *data = ba.data();
        while (*data) {
            cout << "[" << *data << "]" << endl;
            ++data;
        }
        //! [8]
    }
 
    {
        //! [9]
        QByteArray ba("Hello, world");
        cout << ba[0]; // prints H
        ba[7] = 'W';
        // ba == "Hello, World"
        //! [9]
    }
 
    {
        //! [10]
        QByteArray ba("Stockholm");
        ba.truncate(5);             // ba == "Stock"
        //! [10]
    }
 
    {
        //! [11]
        QByteArray ba("STARTTLS\r\n");
        ba.chop(2);                 // ba == "STARTTLS"
        //! [11]
    }
 
    {
        //! [12]
        QByteArray x("free");
        QByteArray y("dom");
        x += y;
        // x == "freedom"
        //! [12]
    }
 
    {
        //! [13]
        QByteArray().isNull();          // returns true
        QByteArray("").isNull();        // returns false
        QByteArray("abc").isNull();     // returns false
        //! [13]
    }
 
    {
        //! [fill]
        QByteArray ba("Istambul");
        ba.fill('o');
        // ba == "oooooooo"
        //! [fill]
    }
    {
        //! [14]
        QByteArray ba("Istambul");
        ba.fill('X', 2);
        // ba == "XX"
        //! [14]
    }
 
    {
        //! [15]
        QByteArray x("ship");
        QByteArray y("air");
        x.prepend(y);
        // x == "airship"
        //! [15]
    }
 
    {
        //! [16]
        QByteArray x("free");
        QByteArray y("dom");
        x.append(y);
        // x == "freedom"
        //! [16]
    }
 
    {
        //! [17]
        QByteArray ba("Meal");
        ba.insert(1, QByteArrayView("ontr"));
        // ba == "Montreal"
        //! [17]
    }
 
    {
        //! [18]
        QByteArray ba("Montreal");
        ba.remove(1, 4);
        // ba == "Meal"
        //! [18]
    }
 
    {
        //! [19]
        QByteArray x("Say yes!");
        QByteArray y("no");
        x.replace(4, 3, y);
        // x == "Say no!"
        //! [19]
    }
 
    {
        //! [20]
        QByteArray ba("colour behaviour flavour neighbour");
        ba.replace(QByteArray("ou"), QByteArray("o"));
        // ba == "color behavior flavor neighbor"
        //! [20]
    }
 
    {
        //! [21]
        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
        //! [21]
    }
 
    {
        //! [22]
        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
        //! [22]
    }
 
    {
        //! [23]
        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
        //! [23]
    }
 
    {
        //! [24]
        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
        //! [24]
    }
 
    {
        //! [25]
        QByteArray url("ftp://ftp.qt-project.org/");
        if (url.startsWith("ftp:"))
            {/*...*/}
        //! [25]
    }
 
    {
        //! [26]
        QByteArray url("http://qt-project.org/doc/qt-5.0/qtdoc/index.html");
        if (url.endsWith(".html"))
            {/*...*/}
        //! [26]
    }
 
    {
        //! [27]
        QByteArray x("Pineapple");
        QByteArray y = x.first(4);
        // y == "Pine"
        //! [27]
    }
 
    {
        //! [28]
        QByteArray x("Pineapple");
        QByteArray y = x.last(5);
        // y == "apple"
        //! [28]
    }
 
    {
        //! [29]
        QByteArray x("Five pineapples");
        QByteArray y = x.sliced(5, 4);     // y == "pine"
        QByteArray z = x.sliced(5);        // z == "pineapples"
        //! [29]
    }
 
    {
        //! [30]
        QByteArray x("Qt by THE QT COMPANY");
        QByteArray y = x.toLower();
        // y == "qt by the qt company"
        //! [30]
    }
 
    {
        //! [31]
        QByteArray x("Qt by THE QT COMPANY");
        QByteArray y = x.toUpper();
        // y == "QT BY THE QT COMPANY"
        //! [31]
    }
 
    {
        //! [32]
        QByteArray ba("  lots\t of\nwhitespace\r\n ");
        ba = ba.simplified();
        // ba == "lots of whitespace";
        //! [32]
    }
 
    {
        //! [33]
        QByteArray ba("  lots\t of\nwhitespace\r\n ");
        ba = ba.trimmed();
        // ba == "lots\t of\nwhitespace";
        //! [33]
    }
 
    {
        //! [34]
        QByteArray x("apple");
        QByteArray y = x.leftJustified(8, '.');   // y == "apple..."
        //! [34]
    }
 
    {
        //! [35]
        QByteArray x("apple");
        QByteArray y = x.rightJustified(8, '.');    // y == "...apple"
        //! [35]
    }
 
    {
        //! [36]
        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
        //! [36]
    }
 
    {
        //! [37]
        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
        //! [37]
    }
 
    {
        //! [38]
        QByteArray string("1234.56");
        bool ok;
        double a = string.toDouble(&ok);   // a == 1234.56, ok == true
 
        string = "1234.56 Volt";
        a = string.toDouble(&ok);             // a == 0, ok == false
        //! [38]
    }
 
    {
        //! [38float]
        QByteArray string("1234.56");
        bool ok;
        float a = string.toFloat(&ok);    // a == 1234.56, ok == true
 
        string = "1234.56 Volt";
        a = string.toFloat(&ok);              // a == 0, ok == false
        //! [38float]
    }
 
    {
        //! [39]
        QByteArray text("Qt is great!");
        text.toBase64();        // returns "UXQgaXMgZ3JlYXQh"
 
        QByteArray hello("<p>Hello?</p>");
        hello.toBase64(QByteArray::Base64Encoding | QByteArray::OmitTrailingEquals);      // returns "PHA+SGVsbG8/PC9wPg"
        hello.toBase64(QByteArray::Base64Encoding);                                       // returns "PHA+SGVsbG8/PC9wPg=="
        hello.toBase64(QByteArray::Base64UrlEncoding);                                    // returns "PHA-SGVsbG8_PC9wPg=="
        hello.toBase64(QByteArray::Base64UrlEncoding | QByteArray::OmitTrailingEquals);   // returns "PHA-SGVsbG8_PC9wPg"
        //! [39]
    }
 
    {
        //! [40]
        QByteArray ba;
        int n = 63;
        ba.setNum(n);           // ba == "63"
        ba.setNum(n, 16);       // ba == "3f"
        //! [40]
    }
 
    {
        //! [41]
        int n = 63;
        QByteArray::number(n);              // returns "63"
        QByteArray::number(n, 16);          // returns "3f"
        QByteArray::number(n, 16).toUpper();  // returns "3F"
        //! [41]
    }
 
    {
        //! [42]
        QByteArray ba = QByteArray::number(12.3456, 'E', 3);
        // ba == 1.235E+01
        //! [42]
    }
 
    {
        //! [43]
        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);
        //...
        //! [43]
    }
 
    {
        //! [44]
        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>"
        //! [44]
    }
 
    QByteArray encodedData;
 
    {
        //! [44ter]
        void process(const QByteArray &);
 
        if (auto result = QByteArray::fromBase64Encoding(encodedData))
            process(*result);
        //! [44ter]
 
        //! [44quater]
        auto result = QByteArray::fromBase64Encoding(encodedData);
        if (result.decodingStatus == QByteArray::Base64DecodingStatus::Ok)
            process(result.decoded);
        //! [44quater]
    }
 
    {
        //! [45]
        QByteArray text = QByteArray::fromHex("517420697320677265617421");
        text.data();            // returns "Qt is great!"
        //! [45]
    }
 
    {
        //! [46]
        QString tmp = "test";
        QByteArray text = tmp.toLocal8Bit();
        char *data = new char[text.size()];
        strcpy(data, text.data());
        delete [] data;
        //! [46]
    }
 
    {
        //! [47]
        QString tmp = "test";
        QByteArray text = tmp.toLocal8Bit();
        char *data = new char[text.size() + 1];
        strcpy(data, text.data());
        delete [] data;
        //! [47]
    }
 
    {
        //! [48]
        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.
        //! [48]
    }
 
    {
        //! [49]
        QByteArray ba("ab");
        ba.repeated(4);             // returns "abababab"
        //! [49]
    }
 
    {
        //! [50]
        QByteArray macAddress = QByteArray::fromHex("123456abcdef");
        macAddress.toHex(':'); // returns "12:34:56:ab:cd:ef"
        macAddress.toHex(0);   // returns "123456abcdef"
        //! [50]
    }
 
    {
        //! [51]
        QByteArray text = QByteArray::fromPercentEncoding("Qt%20is%20great%33");
        qDebug("%s", text.data());      // reports "Qt is great!"
        //! [51]
    }
 
    {
        //! [52]
        QByteArray text = "{a fishy string?}";
        QByteArray ba = text.toPercentEncoding("{}", "s");
        qDebug("%s", ba.constData());
        // prints "{a fi%73hy %73tring%3F}"
        //! [52]
    }
 
    {
        //! [53]
        QByteArray ba = QByteArrayLiteral("byte array contents");
        //! [53]
    }
 
    {
        //! [54]
        QByteArray encoded("Qt%20is%20great%33");
        QByteArray decoded = encoded.percentDecoded(); // Set to "Qt is great!"
        //! [54]
    }
 
    using namespace Qt::StringLiterals;
 
    {
        //! [57]
        QByteArray x = "Five pineapples"_ba;
        x.slice(5);     // x == "pineapples"
        x.slice(4, 3);  // x == "app"
        //! [57]
    }
 
}
 
# ifdef EMSCRIPTEN
#include <emscripten/val.h>
void emscripten_examples()
{
    {
        //! [55]
        emscripten::val uint8array = emscripten::val::global("g_uint8array");
        QByteArray byteArray = QByteArray::fromEcmaUint8Array(uint8array);
        //! [55]
    }
    {
        //! [56]
        QByteArray byteArray = "test";
        emscripten::val uint8array = byteArray.toEcmaUint8Array();
        //! [56]
    }
}
# endif