常用參數:
QIODevice::ReadWrite
QIODevice::ReadOnly
QIODevice::WriteOnly
QIODevice::Text
QIODevice::Append
檔案讀取：
公告版位
需要找什麼嗎? 左邊分類或許可以幫助你...
- Nov 17 Tue 2015 15:04
C++ ( Qt 5 ) 入門範例：檔案讀寫
- Nov 17 Tue 2015 09:25
C++ ( Qt 5 ) 入門範例：各種 Json 範例
寫入Json 物件：
#include<QCoreApplication>
#include<QJsonDocument>
#include<QJsonObject>
#include<QJsonValue>
#include<QJsonArray>
#include<QDebug>
int main(int argc,char * argv[]) {
QCoreApplication a(argc,argv);
QJsonObject jsonObj;
jsonObj.insert("A","aaa");
jsonObj.insert("B","bbb");
//輸出：
QJsonDocument doc(jsonObj);
QString strJson(doc.toJson());
qDebug()<<strJson.toStdString().data();
return a.exec();
}
輸出結果：
----------------------------------------------------------------------------------------------------------
Json 物件單行輸出：
#include<QCoreApplication>
#include<QJsonDocument>
#include<QJsonObject>
#include<QJsonValue>
#include<QJsonArray>
#include<QDebug>
int main(int argc, char * argv[]){
QCoreApplication a(argc,argv);
QJsonObject jsonObj;
jsonObj.insert("A","aaa");
jsonObj.insert("B","bbb");
//輸出：
QJsonDocument doc(jsonObj);
QString strJson(doc.toJson(QJsonDocument::Compact));
qDebug()<<strJson.toStdString().data();
return a.exec();
}
輸出結果：
----------------------------------------------------------------------------------------------------------
Json 巢狀物件：
#include<QCoreApplication>
#include<QJsonDocument>
#include<QJsonObject>
#include<QJsonValue>
#include<QJsonArray>
#include<QDebug>
int main(int argc, char * argv[]){
QCoreApplication a(argc,argv);
QJsonObject country;
country.insert("Japan","HelloKitty");
QJsonObject city;
city.insert("Taipei","101");
country.insert("Taiwan",city);
//輸出：
QJsonDocument doc(country);
QString strJson(doc.toJson(QJsonDocument::Compact));
qDebug()<<strJson.toStdString().data();
return a.exec();
}
輸出結果：
----------------------------------------------------------------------------------------------------------
Json 陣列：
- Nov 16 Mon 2015 00:08
C++ ( Qt 5 ) 入門範例：Http 檔案下載
#include<QCoreApplication>
#include<QDebug>
#include<QtNetwork/QNetworkAccessManager>
#include<QtNetwork/QNetworkRequest>
#include<QtNetwork/QNetworkReply>
#include<QUrl>
#include<QUrlQuery>
#include<QFile>
void sendRequest(){
QEventLoop eventLoop;
QNetworkAccessManager mgr;
QObject::connect(&mgr,SIGNAL(finished(QNetworkReply*)),&eventLoop,SLOT(quit()));
QNetworkRequest req(QUrl(QString("http://i39.tinypic.com/1yn3wx.jpg")));
QNetworkReply * reply = mgr.get(req);
eventLoop.exec();
if(reply->error()==QNetworkReply::NoError){
//連接成功
qDebug()<<"Download...";
QFile * file = new QFile("C:/Test/downloaded.jpg");
if(file->open(QFile::Append)) {
file->write(reply->readAll());
file->flush();
file->close();
}
delete file;
qDebug() << "ok";
}else{
//連接失敗
qDebug() << "Failure" <<reply -> errorString();
}
delete reply;
}
intmain(int argc, char * argv[]) {
QCoreApplication a(argc,argv);
sendRequest();
return a.exec();
}
- Nov 15 Sun 2015 23:35
C++ ( Qt 5 ) 入門範例：Sleep 暫停
#include <QCoreApplication>
#include <QDebug>
#include "windows.h" // Windows
// #include "#include <sys/stat.h>" // Linux
intmain(int argc, char * argv[]){
QCoreApplication a(argc,argv);
QString msg;
for(int i=1;i<=10;i++){
msg.sprintf("Hello:%d",i);
qDebug()<<msg.toStdString().c_str();
Sleep(1000);
}
returna.exec();
}
也可以參考：http://blog.csdn.net/dbzhang800/article/details/6300425
- Nov 15 Sun 2015 22:51
C++ ( Qt 5 ) 入門範例：Http 接收資料
#include<QCoreApplication>
#include<QDebug>
#include<QtNetwork/QNetworkAccessManager>
#include<QtNetwork/QNetworkRequest>
#include<QtNetwork/QNetworkReply>
#include<QUrl>
#include<QUrlQuery>
void sendRequest() {
QEventLoop eventLoop;
QNetworkAccessManager mgr;
QObject::connect(&mgr,SIGNAL(finished(QNetworkReply*)),&eventLoop,SLOT(quit()));
QNetworkRequest req(QUrl(QString("http://ip.jsontest.com/")));
QNetworkReply * reply=mgr.get(req);
eventLoop.exec();
if(reply->error()==QNetworkReply::NoError){
//連接成功
qDebug()<<"Success"<<reply->readAll();
} else {
//連接失敗
qDebug()<<"Failure"<<reply->errorString();
}
delete reply;
}
int main(int argc, char * argv[]) {
QCoreApplication a(argc, argv);
sendRequest();
return a.exec();
}
