QT记事本的读写函数
头文件：
#include <QMessageBox>
#include <QtDebug>
#include <QFile>
#include <QFileDialog>
#include <QDir>
#include <QTextStream>
私有数据成员：
QString fileString;//数据成员，保存要打开的文件名
构造函数添加的信号与槽链接：
QObject::connect(ui->openAction,SIGNAL(triggered()),this,SLOT(openFileSlot()));//记事本的打开(O)信号与槽进行连接，openAction是打开(O)的对象名
QObject::connect(ui->saveAction,SIGNAL(triggered()),this,SLOT(saveFileSlot()));//记事本的保存(S)信号与槽进行连接，saveAction是保存(S)的对象名
函数：
oid MainWindow::openFileSlot()
{
fileName = QFileDialog::getOpenFileName(this,"Open File",QDir::currentPath());//获取要打开文件的绝对路径
if (fileName.isEmpty())//判断是否为空
{
QMessageBox::information(this,"ERROR MESSAGE","Please selete a file");
return;
}
QFile *file = new QFile;
file->setFileName(fileName);
bool ok = file->open(QIODevice::ReadOnly);//以只读方式打开文件
if (ok)
{
QTextStream in(file);
ui->textEdit->setText(in.readAll());//读取文件所有内容
file->close();
delete file;
}
else
{
QMessageBox::warning(this,"ERROR MESSAGE","File Open FiLE"+file->errorString());
return;
}
}
void MainWindow::saveFileSlot()
{
if (fileName.isEmpty())
{
QMessageBox::warning(this,"ERROR MESSAGE","Please selete a file");
return;
}
else
{
QFile *file = new QFile;
file->setFileName(fileName);
bool ok = file->open(QIODevice::WriteOnly);
if (ok)
{
QTextStream out(file);
out << ui->textEdit->toPlainText();
file->close();
delete file;
}
else
{
QMessageBox::information(this,"ERROR MESSAGE","save file error");
return;
}
}
}