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I've been using QString::number () to convert numbers to string for long time , now i'm wondering if there's something better than following:
int i = 0;
QString msg = QString ("Loading %1").arg (QString::number (i));
How can i spare QString::number () ? i checked document , seems only "%1" is applicable , no other stuff like "%d" could work
777
To break up a string into a string list, we used the QString::split() function. The argument to split can be a single character, a string, or a QRegExp. To concatenate all the strings in a string list into a single string (with an optional separator), we used the join() function.
Generally speaking: If you want to initialize a QString from a char*, use QStringLiteral . If you want to pass it to a method, check if that method has an overload for QLatin1String - if yes you can use that one, otherwise fall back to QStringLiteral .
The QString class provides an abstraction of Unicode text and the classic C '\0'-terminated char array. More... All the functions in this class are reentrant when Qt is built with thread support.
QString's arg() function does indeed implement many different types and automatically detect what you provide it. Providing multiple parameters to a single arg() call like so
// Outputs "one two three"
QString s = QString("%1 %2 %3").arg("one", "two", "three")
is only implemented for QString (and hence const char*) parameters.
However, you can chain arg calls together and still use the numbering system:
int i = 5;
size_t ui = 6;
int j = 12;
// Outputs "int 5 size_t 6 int 12"
qDebug() << QString("int %1 size_t %2 int%3").arg(i).arg(ui).arg(j);
// Also outputs "int 5 size_t 6 int 12"
qDebug() << QString("int %1 int %3 size_t %2").arg(i).arg(j).arg(ui);
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