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QFile
#ifndef WIDGET_H
#define WIDGET_H
#include <QWidget>
namespace Ui {
class Widget;
}
class Widget : public QWidget
{
Q_OBJECT
public:
explicit Widget(QWidget *parent = 0);
~Widget();
private slots:
void on_readButton_clicked();
void on_writeButton_clicked();
private:
Ui::Widget *ui;
};
#endif // WIDGET_H
#include "widget.h"
#include "ui_widget.h"
#include <QFileDialog>
#include <QFileInfo>
#include <QDateTime>
#include <QDebug>
#include <QDataStream>
Widget::Widget(QWidget *parent) :
QWidget(parent),
ui(new Ui::Widget)
{
ui->setupUi(this);
}
Widget::~Widget()
{
delete ui;
}
void Widget::on_readButton_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)
{
#if 0
//默认只识别utf8编码
QByteArray array = file.readAll();
//ui->textEdit->setText(QString(array));
ui->textEdit->setText(array);
#endif
QByteArray array;
while (file.atEnd() == false)
{
array += file.readLine();
}
ui->textEdit->setText(array);
}
file.close();
QFileInfo info(path);
qDebug()<<info.fileName();
qDebug()<<info.suffix();
qDebug()<<info.size();
qDebug()<<info.created().toString("yyyy-MM-dd hh:mm:ss");
}
}
void Widget::on_writeButton_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();
}
}
QDataStream
#ifndef WIDGET_H
#define WIDGET_H
#include <QWidget>
namespace Ui {
class Widget;
}
class Widget : public QWidget
{
Q_OBJECT
public:
explicit Widget(QWidget *parent = 0);
~Widget();
void writeData();
void readData();
private:
Ui::Widget *ui;
};
#endif // WIDGET_H
#include "widget.h"
#include "ui_widget.h"
#include <QDataStream>
#include <QTextStream>
#include <QFile>
#include <QDebug>
#define cout qDebug()<<"["<<__FILE__<<":"<<__LINE__<<"]"
Widget::Widget(QWidget *parent) :
QWidget(parent),
ui(new Ui::Widget)
{
ui->setupUi(this);
writeData();
readData();
}
Widget::~Widget()
{
delete ui;
}
void Widget::writeData()
{
QFile file("../fff.txt");
bool isOK = file.open(QIODevice::WriteOnly);
if (true == isOK)
{
//创建数据流，和file文件关联
//往数据流中写数据，相当于往文件里写数据
QDataStream stream(&file);
stream<<QString("hello world")<<250;
}
file.close();
}
void Widget::readData()
{
QFile file("../fff.txt");
bool isOK = file.open(QIODevice::ReadOnly);
if (true == isOK)
{
//创建数据流，和file文件关联
//往数据流中读数据，相当于往文件里写数据
QString str;
int a;
QDataStream stream(&file);
stream>>str>>a;
cout<<str<<a;
}
file.close();
}
QTextStream
#ifndef WIDGET_H
#define WIDGET_H
#include <QWidget>
namespace Ui {
class Widget;
}
class Widget : public QWidget
{
Q_OBJECT
public:
explicit Widget(QWidget *parent = 0);
~Widget();
void writeData();
void readData();
private slots:
void on_pushButton_clicked();
private:
Ui::Widget *ui;
};
#endif // WIDGET_H
#include "widget.h"
#include "ui_widget.h"
#include <QFile>
#include <QTextStream>
#include <QDebug>
#include <QFileDialog>
#define cout qDebug()<<"["<<__FILE__<<":"<<__LINE__<<"]"
Widget::Widget(QWidget *parent) :
QWidget(parent),
ui(new Ui::Widget)
{
ui->setupUi(this);
writeData();
readData();
}
Widget::~Widget()
{
delete ui;
}
void Widget::writeData()
{
QFile file;
file.setFileName("../demo.txt");
bool isOK = file.open(QIODevice::WriteOnly);
if(true == isOK)
{
QTextStream stream(&file);
//指定编码
stream.setCodec("UTF-8");
stream << QString("hello world")<<250;
file.close();
}
}
void Widget::readData()
{
//这么读有问题
QFile file;
file.setFileName("../demo.txt");
bool isOK = file.open(QIODevice::ReadOnly);
if(true == isOK)
{
QTextStream stream(&file);
//指定编码
stream.setCodec("UTF-8");
QString str;
int a;
stream >>str>>a;
cout<<str<<a;
file.close();
}
}
void Widget::on_pushButton_clicked()
{
QString path = QFileDialog::getOpenFileName(this,
"read",
"../"
);
if(false == path.isEmpty())
{
QFile file;
file.setFileName(path);
bool isOK = file.open(QIODevice::ReadOnly);
if(true == isOK)
{
QTextStream stream(&file);
stream.setCodec("UTF-8");
QString str = stream.readAll();
ui->textEdit->setText(str);
file.close();
}
}
}
QBuffer
#ifndef WIDGET_H
#define WIDGET_H
#include <QWidget>
namespace Ui {
class Widget;
}
class Widget : public QWidget
{
Q_OBJECT
public:
explicit Widget(QWidget *parent = 0);
~Widget();
private:
Ui::Widget *ui;
};
#endif // WIDGET_H
#include "widget.h"
#include "ui_widget.h"
#include <QBuffer>//内存文件
#include <QDebug>
Widget::Widget(QWidget *parent) :
QWidget(parent),
ui(new Ui::Widget)
{
ui->setupUi(this);
QBuffer memFile;
memFile.open(QIODevice::WriteOnly);
memFile.write("hello");
memFile.write("world");
memFile.close();
qDebug()<<memFile.buffer();
QBuffer memFile1;
memFile1.open(QIODevice::WriteOnly);
QDataStream stream(&memFile1);
stream<<QString("测试")<<250;
memFile1.close();
qDebug()<<QString(memFile.buffer()).toUtf8().data();//输出有问题
//输出正确
memFile1.open(QIODevice::ReadOnly);
QDataStream in(&memFile1);
QString str;
int a;
in>>str>>a;
memFile1.close();
qDebug()<<str.toUtf8().data()<<a;
}
Widget::~Widget()
{
delete ui;
}