1、代码：
void MainWindow::on_pushButton_clicked()
{
QString str = "5";
QString str01 = str.leftJustified(3, ‘0‘);
qDebug() << str01;
str01 = str.rightJustified(5, ‘0‘);
qDebug() << str01;
str01 = str.rightJustified(2, ‘0‘);
qDebug() << str01;
}
2、控制台输出：
"500" "00005" "05"
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转载于:https://www.cnblogs.com/cppskill/p/8085270.html