QFile文件读写

参考代码

　　.h文件

 1 #ifndef MYWIDGET_H
 2 #define MYWIDGET_H
 3 
 4 #include <QWidget>
 5 #include <QFile>
 6 #include <QFileDialog>
 7 namespace Ui {
 8 class myWidget;
 9 }
10 
11 class myWidget : public QWidget
12 {
13     Q_OBJECT
14 
15 public:
16     explicit myWidget(QWidget *parent = 0);
17     ~myWidget();
18 
19 private slots:
20     void on_read_clicked();
21 
22     void on_write_clicked();
23 
24 private:
25     Ui::myWidget *ui;
26 };
27 
28 #endif // MYWIDGET_H

　　.cpp文件

 1 #include "mywidget.h"
 2 #include "ui_mywidget.h"
 3 
 4 myWidget::myWidget(QWidget *parent) :
 5     QWidget(parent),
 6     ui(new Ui::myWidget)
 7 {
 8     ui->setupUi(this);
 9     setWindowTitle("QFile文件读写");
10 }
11 
12 myWidget::~myWidget()
13 {
14     delete ui;
15 }
16 
17 void myWidget::on_read_clicked()
18 {
19 QString path = QFileDialog::getOpenFileName(this,"open","../","TXT(*.txt)");
20 if(path.isEmpty()==false)
21 {
22     QFile file(path);
23     bool isOK = file.open(QIODevice::ReadOnly);
24             if(isOK==true)
25             {//方法1
26 //                QByteArray array = file.readAll();
27 //                ui->textEdit->setText(QByteArray(array));
28 
29                 QByteArray array;//方法2
30                 while(file.atEnd()==false)
31                 {
32                     array += file.readLine();
33                 }
34                 ui->textEdit->setText(array);
35             }
36             file.close();
37 
38 }
39 }
40 
41 void myWidget::on_write_clicked()
42 {
43     QString path = QFileDialog::getSaveFileName(this,"save","../","TXT(*.txt)");
44     if(path.isEmpty()==false)
45     {
46         QFile file;
47         file.setFileName(path);
48         bool isOK = file.open(QIODevice::WriteOnly);
49         if(isOK==true)
50         {
51           QString str = ui->textEdit->toPlainText();
52           //file.write(str.toUtf8());
53           file.write(str.toStdString().data());
54         }
55         file.close();
56     }
57 
58 }