QString和string互相转换中文字符

string -> QString

1 std::string strStd = "可可西";
2 QString strQ = QString::fromLocal8Bit(strStd.c_str());

QString -> string

1 QString strQ("可可西");
2 std::string strStd= strQ.toStdString();
3 QTextCodec *code = QTextCodec::codecForName("gb18030");
4  // 如果code为0，表示在运行的机器上没有装gb18030字符集。不过一般的中文windows系统中都安装了这一字符集
5  if (code)    strStd= code->fromUnicode(strQ).data();

转自：http://www.th7.cn/Program/cp/2011-07-07/30434.shtml

先看看官方是如何说的：

How can I convert a QString to char* and vice versa ?(trolltech)

Answer:

In order to convert a QString to a char*, then you first need to get a latin1 representation of the string by calling toLatin1() on it which will return a QByteArray. Then call data() on the QByteArray to get a pointer to the data stored in the byte array.
See the documentation:

See the following example for a demonstration:

int main(int argc, char **argv)

{

QApplication app(argc, argv);

QString str1 = "Test";

QByteArray ba = str1.toLatin1();

const char *c_str2 = ba.data();

printf("str2: %s", c_str2);

return app.exec();

}

Note that it is necessary to store the bytearray before you call data() on it, a call like the following

const char *c_str2 = str2.toLatin1().data();

will make the application crash as the QByteArray has not been stored and hence no longer exists.

To convert a char* to a QString you can use the QString constructor that takes a QLatin1String, e.g:

QString string = QString(QLatin1String(c_str2)) ;

还有其他多种方法：

方法一 -----------------------------------------

#define G2U(s) ( QTextCodec::codecForName("GBK")->toUnicode(s) )

#define U2G(s) ( QTextCodec::codecForName("GBK")->fromUnicode(s) )

QString str;

QCString cstr;

str = G2U("中文输入");

cstr = U2G(str);

QCString有这样一个重载运算符

operator const char * () const

可以这样

printf("%s\n", (const char*) cstr);

或是copy出来

char buf[1024];

strcpy(buf, (const char*) cstr);

方法二 -----------------------------------------

如果是中文系统

直接用 (const char*) str.local8Bit()

例如

printf("%s", (const char*) str.local8Bit());

str是一个QString

方法三 -----------------------------------------

char str[64];

QTextCodec *textcod = QTextCodec::codecForName("GBK");

QCString string1 = textcod ->fromUnicode(listbox1->currentText());

strcpy(str,string1);

QString和Std::string

从char*到 QString可以从fromLocal8Bit()转化

std::string有c_str()的函数使再转化为char*

QString有toAscii()记不清了

你可以看看.

又是我的粗心酿成大错，我重新查看了一下Qt文档，原来Qt可以直接从std::wstring产生一个QString，用QString::fromStdWString(const std::wstring &)这个静态成员函数即可。我试了试用std::string的c_str()返回的char *构造的QString不能再保存原先的中文信息，而用std::wstring构造的QString则可以用qDebug()输出原先的中文信息

GB编码与UTF8编码的转换

在主函数app后加上这句：

QUOTE:

QTextCodec::setCodecForLocale(QTextCodec::codecForName("GB18030"));

然后是从UTF8编码到GB编码的字符串转换方法：

QUOTE:

QString Utf8_To_GB(QString strText)

{

return QString::fromUtf8(strText.toLocal8Bit().data());

}

至于从GB到UTF8，那大家就经常用了：

QUOTE:

QString GB_To_Utf8(char *strText)

{

return QString::fromLocal8Bit(strText);

}

转自：http://blog.sina.com.cn/s/blog_3fd731da01009fgx.html