QT5学习：字符串测试

#include <QCoreApplication>
#include <QTextStream>
#include <stdio.h>
#include <iostream>
#include <QDebug>

QTextStream cin(stdin, QIODevice::ReadOnly);
QTextStream cout(stdout, QIODevice::WriteOnly);
QTextStream cerr(stderr, QIODevice::WriteOnly);

int main(int argc, char *argv[])
{
QCoreApplication a(argc, argv);

QString str1 = "Hello";
str1 += " world";
//label2->setText(str1);
QByteArray ba1 = str1.toLatin1();
printf("ba1==%s\n",ba1.data());
QString str2;
str2 = QString("%1 is good %2").arg("QT").arg("Language");
QByteArray ba2 = str2.toLatin1();
printf(ba2.data());

/////////////////////////////////测试字符串char*转QString
const char *cstr = "hello";
QString qstr= QString(QLatin1String(cstr));
cout << "\tqstr==" << qstr << endl;//必须加endl才能输出

/////////////////////////////////测试字符串函数
QString str3 = "hello";
str3.insert(1,"world");
cout << str3 << endl;//必须加endl才能输出
QString str4 = "hello";
str4.prepend("world");
cout << str4 << endl;//必须加endl才能输出
QString str5 = "hello";
str5.replace(1,2,"ww");
//label2->setText(str5);
cout << "str5==" << str5 << endl;//必须加endl才能输出
printf("a==%s\n",str5);

/////////////////////////////////测试字符串
QString str6 = "hello,world";
QByteArray ba6 = str6.toLatin1();//toAscii()返回一个QByteArray类型
const char* strData = ba6.data();
//std::cout << strData << endl;//QT中：std::cout输出有问题、后面跟一堆乱七八糟的数字
//cout << "strData==" << strData << endl;
qDebug() << "strData==" << strData;//qDebug也可以输出语句
//其它类型变量还是可以照常输出的。
QString str7 = "125";
bool ok;
int iValue7 = str7.toInt(&ok, 16);//0x125==293
qDebug() << "iValue7==" << iValue7 << endl;

return a.exec();
}