QFile文件读写

• 参考代码

　　.h文件

 #ifndef MYWIDGET_H
 #define MYWIDGET_H

 #include <QWidget>
 #include <QFile>
 #include <QFileDialog>
 namespace Ui {
 class myWidget;
 }

 class myWidget : public QWidget
 {
     Q_OBJECT

 public:
     explicit myWidget(QWidget *parent = );
     ~myWidget();

 private slots:
     void on_read_clicked();

     void on_write_clicked();

 private:
     Ui::myWidget *ui;
 };

 #endif // MYWIDGET_H

　　.cpp文件

 #include "mywidget.h"
 #include "ui_mywidget.h"

 myWidget::myWidget(QWidget *parent) :
     QWidget(parent),
     ui(new Ui::myWidget)
 {
     ui->setupUi(this);
     setWindowTitle("QFile文件读写");
 }

 myWidget::~myWidget()
 {
     delete ui;
 }

 void myWidget::on_read_clicked()
 {
 QString path = QFileDialog::getOpenFileName(this,"open","../","TXT(*.txt)");
 if(path.isEmpty()==false)
 {
     QFile file(path);
     bool isOK = file.open(QIODevice::ReadOnly);
             if(isOK==true)
             {//方法1
 //                QByteArray array = file.readAll();
 //                ui->textEdit->setText(QByteArray(array));

                 QByteArray array;//方法2
                 while(file.atEnd()==false)
                 {
                     array += file.readLine();
                 }
                 ui->textEdit->setText(array);
             }
             file.close();

 }
 }

 void myWidget::on_write_clicked()
 {
     QString path = QFileDialog::getSaveFileName(this,"save","../","TXT(*.txt)");
     if(path.isEmpty()==false)
     {
         QFile file;
         file.setFileName(path);
         bool isOK = file.open(QIODevice::WriteOnly);
         if(isOK==true)
         {
           QString str = ui->textEdit->toPlainText();
           //file.write(str.toUtf8());
           file.write(str.toStdString().data());
         }
         file.close();
     }

 }