从一个E:\\test.txt读入数据，一行行读，然后保存大于等于第二行的数据到e:\\output_file.txt <pre class='brush: cpp'>#include <QApplication> #include <QFile> #include <QDebug> int main(int argc, char *argv[]) { QApplication a(argc, argv); MainWindow w; w.show(); QFile file_data("E:\\test.txt"); QFile output_file("E:\\output_file.txt"); if(!file_data.open(QIODevice::ReadOnly) || !output_file.open(QIODevice::WriteOnly | QIODevice::Text | QIODevice::Append)) { qDebug() <<"read or output file don't exist!"; } else { int i = 1; QTextStream in(&output_file); while(!file_data.atEnd()) { QByteArray line = file_data.readLine(); QString str(line); if(str.right(2) == "\r\n")//因为readline连换行符也会读进来，WINDOWS下换行是\r\n str = str.left(str.size() - 2); if(i++ >= 2) in << str << "\n"; } } file_data.close(); output_file.close(); return a.exec(); }</pre>