最近在搞Qt的網絡通信和音樂播放的應用，做完每一個部分都會上傳上來。下面的這段代碼中實現了訪問百度主頁，返回的信息可以再輸出窗查看，代碼中註釋的部分是上傳文件用的。QNetworkAccessManager是Qt4.4裏才引入的類，qt4,.4之前一般都是使用QHttp實現。
類申明：
#ifndef DIALOG_H
#define DIALOG_H
#include <QtGui/QDialog>
#include <QNetworkAccessManager>
#include <QFile>
#include <QNetworkReply>
#include <QNetworkRequest>
#include <QPushButton>
#include <QHBoxLayout>
#include <QIODevice>
/********************HTTP實現通信******************************/
/*************************************************************/
/*************************************************************/
/*************************************************************/
class Dialog : public QDialog
{
Q_OBJECT
public:
Dialog(QWidget *parent = 0);
~Dialog();
protected slots:
void httpDownload();
void replyFinished(QNetworkReply*reply);
void onUploadProgress(qint64 bytesSent,qint64 butesTotal);
private:
QPushButton *download_Btn;
QFile *file;
QNetworkAccessManager *accessManager;
QNetworkRequest request;
QNetworkReply *reply;
QHBoxLayout *layout;
};
#endif // DIALOG_H
類的實現：
#include "dialog.h"
#include<QtDebug>
Dialog::Dialog(QWidget *parent)
: QDialog(parent)
{
download_Btn=new QPushButton("download");
layout=new QHBoxLayout();
layout->addWidget(download_Btn);
layout->sizeHint().height();
setLayout(layout);
connect(download_Btn,SIGNAL(clicked()),this,SLOT(httpDownload()));
}
Dialog::~Dialog()
{
}
void Dialog::httpDownload(){
//QUrl url("http://localhost:8080/uploadtest/MyUpload");
QUrl url("http://www.baidu.com");
QByteArray post_data;//上傳的數據可以是QByteArray或者file類型
post_data.append("hello");
file=new QFile("/home/vino/Desktop/a.txt");
file->open(QIODevice::ReadOnly);//只讀方式打開文件
accessManager=new QNetworkAccessManager(this);
request.setUrl(url);
/******************設置http的header***********************/
// request.setHeader(QNetworkRequest::ContentTypeHeader, "multipart/form-data");
// request.setHeader(QNetworkRequest::ContentTypeHeader, "application/octet-stream");//上傳文件
// request.setRawHeader("Content-Disposition","form-data;name='doc';filename='a.txt'");
//request.setHeader(QNetworkRequest::ContentLengthHeader,post_data.length());
connect(accessManager, SIGNAL(finished(QNetworkReply*)), this, SLOT(replyFinished(QNetworkReply*)));//finish爲manager自帶的信號，replyFinished是自定義的
reply=accessManager->post(request,post_data);//通過發送數據，返回值保存在reply指針裏.
//connect(reply, SIGNAL(uploadProgress ( qint64 ,qint64 )), this, SLOT( onUploadProgress(qint64 ,qint64 ));//上傳文件時進度 //void QNetworkReply::downloadProgress ( qint64 bytesReceived, qint64 bytesTotal ) qt也有提供下載文件的進度
}
void Dialog::replyFinished(QNetworkReply *reply){
//獲取響應的信息，狀態碼爲200表示正常
QVariant status_code = reply->attribute(QNetworkRequest::HttpStatusCodeAttribute);
//無錯誤返回
if(reply->error() == QNetworkReply::NoError)
{
download_Btn->setText("success");
QByteArray bytes = reply->readAll();
QString result(bytes); //轉化爲字符串
qDebug()<<result;
}
else
{
//處理錯誤
download_Btn->setText("failed");
}
reply->deleteLater();//要刪除reply，但是不能在repyfinished裏直接delete，要調用deletelater;
}
void Dialog::onUploadProgress(qint64 bytesSent, qint64 butesTotal){ //文件上傳的進度
}
主函數：由Qtcreator自動生成
#include <QtGui/QApplication>
#include "dialog.h"
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
Dialog w;
w.show();
return a.exec();
}