QT实现文件读写

#ifndef WIDGET_H
#define WIDGET_H

#include 

QT_BEGIN_NAMESPACE
namespace Ui { class Widget; }
QT_END_NAMESPACE

class Widget : public QWidget
{
    Q_OBJECT

public:
    Widget(QWidget *parent = nullptr);
    ~Widget();

private slots:
    void on_pushButtonRead_clicked();

    void on_pushButtonWrite_clicked();

private:
    Ui::Widget *ui;
};
#endif // WIDGET_H

#include "widget.h"
#include "ui_widget.h"
#include 
#include 
//文件对话框

Widget::Widget(QWidget *parent)
    : QWidget(parent)
    , ui(new Ui::Widget)
{
    ui->setupUi(this);
}

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

//读文件
void Widget::on_pushButtonRead_clicked()
{
    QString path=QFileDialog::getOpenFileName(this,"Open File","../","TXT (*.txt)");
    if(path.isEmpty()==false)
    {
        QFile file(path);
        //打开文件，以只读的方式
        bool isopen=file.open(QIODevice::ReadOnly);
        //如果打开成功，读文件
        if( isopen==true )
        {
            QByteArray msg=file.readAll();
            ui->textEdit->setText(msg);
        }
        file.close();
    }

}

//写文件
void Widget::on_pushButtonWrite_clicked()
{
    QString path1=QFileDialog::getSaveFileName(this,"save file","../","TXT (*.txt)");
    if(path1.isEmpty()==false)
    {
        QFile filewrite;
        filewrite.setFileName(path1);
        bool iswrite=filewrite.open(QIODevice::WriteOnly);
        if(iswrite==true)
        {
            QString str=ui->textEdit->toPlainText();
            filewrite.write(str.toUtf8());
        }
        filewrite.close();
    }

}