Qfile

打开方式：

void AddStudents::write_to_file(QString src){
    QFile file("stu.txt");
    if (!file.open(QIODevice::Append | QIODevice::Text)){
        QMessageBox::critical(this,"打开文件错误","确认");
        return;
    }
    QTextStream out(&file);
    out << src;

}

    if(context.length() != 0 && name != "" && id !="" && ins.length()!= 0){
        int res = QMessageBox::information(this,"请确认信息",context,"确认","取消");
        if(res == 0){
            //点击确定
            //由于准备采用readline的方式来读取文件，所以不能是用'\n'来拼接字符串，换成' '符号来拼接
            QString src_s = name +' ' + id+' '+sex+' '+sche+' '+age+' '+ins;
            write_to_file(src_s);
            //恢复添加界面属性值为初始值
            clear_on_addstudent_ok();
        }
    }else{
        QMessageBox::critical(this,"请确认信息","信息不完整，请重新输入！","确认","取消");
        //重新设置光标位置。这里设置name对应的lineEdit控件获取光标
        this->ui->lineedit_name->setFocus();
    }