C#中，有下列函数可以简单地读写文件：
读:  temp = File.ReadAllText("abc.txt",Encoding.Default);  
写:  File.WriteAllText("abc.txt", temp, Encoding.Default);
追加: File.AppendAllText("abc.txt", temp, Encoding.Default);

现在我也来用Qt彷写一个，以后读写简单的文本文件就不用这么麻烦啦。

#include <QtCore>

class RWFile
{
public:
	/*
	fileName: 要读写的文件名
	text: 要写入（或被写入的字符串）
	codec: 文字编码
	返回值: 失败就返回false, 成功则返回true
	*/
	static bool ReadAllText(const QString &fileName, QString &text,
		const char *codec=NULL);
	static bool WriteAllText(const QString &fileName, const QString &text,
		const char *codec=NULL);
	static bool AppendAllText(const QString &fileName, const QString &text,
		const char *codec=NULL);
};

bool RWFile::ReadAllText(const QString &fileName, QString &text, const char *codec)
{
	QFile file(fileName);
	if( !file.open(QIODevice::ReadOnly) )
		return false;
	QTextStream in(&file);
	if( codec != NULL )
		in.setCodec(codec);
	text = in.readAll();
	file.close();
	return true;
}

bool RWFile::WriteAllText(const QString &fileName, const QString &text, const char *codec)
{
	QFile file(fileName);
	if( !file.open(QIODevice::WriteOnly) )
		return false;
	QTextStream out(&file);
	if( codec != NULL )
		out.setCodec(codec);
	out << text;
	file.close();
	return true;
}

bool RWFile::AppendAllText(const QString &fileName, const QString &text, const char *codec)
{
	QFile file(fileName);
	if( !file.open(QIODevice::Append) )
		return false;
	QTextStream out(&file);
	if( codec != NULL )
		out.setCodec(codec);
	out << text;
	file.close();
	return true;
}

int main(int argc, char **argv)
{
	QCoreApplication app(argc, argv);
	QString temp("abcde");
	bool ok1, ok2, ok3;
	ok1 = RWFile::WriteAllText("abc.txt", temp, "UTF-8");
	ok2 = RWFile::AppendAllText("abc.txt", temp, "UTF-8");
	ok3 = RWFile::ReadAllText("abc.txt", temp, "UTF-8");
	if( ok1 && ok2 && ok3 )
	{
		qDebug() << temp;
	}
	return 0;
}