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() !=  && name != "" && id !="" && ins.length()!= ){  
     int res = QMessageBox::information(this,"请确认信息",context,"确认","取消");  
     if(res == ){  
         //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();  
 }