#include "mainwindow.h"

#include "ui_mainwindow.h"

#include <QFileDialog>

#include <QMessageBox>

#include <QTextStream>

#include <QTextCodec>

MainWindow::MainWindow(QWidget *parent) :

QMainWindow(parent),

ui(new Ui::MainWindow)

{

ui->setupUi(this);

edit = new QTextEdit(this);

edit->setGeometry(QRect(50,50,240,26));

browseBt = new QPushButton(this);

browseBt->setGeometry(QRect(290,50,80,25));

browseBt->setText("浏览文件");

connect(browseBt,SIGNAL(clicked(bool)),this,SLOT(browseFile()));

//显示文件内容

content = new QTextEdit(this);

content->setGeometry(QRect(50,80,320,150));

//修改完毕后，保存文件

saveBt = new QPushButton(this);

saveBt->setGeometry(QRect(290,240,80,25));

saveBt->setText("保存");

connect(saveBt,SIGNAL(clicked()),this,SLOT(saveFile()));

}

//浏览文件

void MainWindow::browseFile()

{

//定义变量 str 接收 QFileDialog 对话框获取的文件路径

QString str = QFileDialog::getOpenFileName(this,"open file","/","textfile(*.txt);;C file(*.cpp);;All file(*.*)");

//将变量绑定 QTextEdit 控件

edit->setText(str.toUtf8());

//判断是否选择文件

if(edit->toPlainText().isEmpty())

{

return;

}

QFile file(edit->toPlainText());

//判断文件是否打开成功

if(!file.open(QIODevice::ReadOnly|QIODevice::Text))

{

QMessageBox::warning(this,"打开文件","打开文件失败！");

return;

}

QTextStream ts(&file);

//循环文档数据至结尾

while(!ts.atEnd())

{

//将全部数据绑定至 content 控件

content->setPlainText(ts.readAll());

}

//关闭文档

file.close();

}

//保存文件

void MainWindow::saveFile()

{

QFile file(edit->toPlainText());

file.open(QIODevice::ReadWrite | QIODevice::Text);

//写入内容,这里需要转码，否则报错。

QByteArray str = content->toPlainText().toUtf8();

//写入 QByteArray 格式字符串

file.write(str);

//提示成功

QMessageBox::warning(this,"修改文件","文件修改成功！");

file.close();

}

MainWindow::~MainWindow()

{

delete ui;

}