转载：C++通过HTTP请求Get或Post方式请求Json数据
最近在工作中，由于合作商只提供uRL，我这边需要通过HTTP请求Get或Post方式请求Json数据，然后解析JSON格式，解析json我使用的第三方库jsoncpp，代码如下
#pragma once#include <iostream>#include <windows.h>#include <wininet.h>using namespace std;//每次读取的字节数#define READ_BUFFER_SIZE 4096enum HttpInterfaceError{Hir_Success = 0, //成功Hir_InitErr, //初始化失败Hir_ConnectErr, //连接HTTP服务器失败Hir_SendErr, //发送请求失败Hir_QueryErr, //查询HTTP请求头失败Hir_404,//页面不存在Hir_IllegalUrl, //无效的URLHir_CreateFileErr, //创建文件失败Hir_DownloadErr, //下载失败Hir_QueryIPErr, //获取域名对应的地址失败Hir_SocketErr, //套接字错误Hir_UserCancel, //用户取消下载Hir_BufferErr, //文件太大，缓冲区不足Hir_HeaderErr, //HTTP请求头错误Hir_ParamErr, //参数错误，空指针，空字符Hir_UnknowErr,};enum HttpRequest{Hr_Get,Hr_Post};class CWininetHttp{public:CWininetHttp(void);~CWininetHttp(void);public:// 通过HTTP请求：Get或Post方式获取JSON信息 [3/14//shike]const std::string RequestJsonInfo( const std::string& strUrl,HttpRequest type = Hr_Get, std::string lpHeader = "",std::string lpPostData = "");protected:// 解析卡口Json数据 [3/14//shike]void ParseJsonInfo(const std::string &strJsonInfo);// 关闭句柄 [3/14//shike]void Release();// 释放句柄 [3/14//shike]void ReleaseHandle( HINTERNET& hInternet );// 解析URL地址 [3/14//shike]void ParseURLWeb( std::string strUrl, std::string& strHostName, std::string& strPageName, WORD& sPort);// UTF-8转为GBK2312 [3/14//shike]char* UtfToGbk(const char* utf8);private:HINTERNET m_hSession;HINTERNET m_hConnect;HINTERNET m_hRequest;HttpInterfaceError m_error;};
/*************************************************File name : WininetHttp.cppDescription: 通过URL访问HTTP请求方式获取JSONAuthor: shikeVersion : 1.0Date : /10/27Copyright (C) - All Rights Reserved*************************************************/#include "WininetHttp.h"//#include "Common.h"#include <json/json.h>#include <fstream>#include "common/CVLog.h"#pragma comment(lib, "Wininet.lib")#include <tchar.h>using namespace std;extern CCVLog CVLog;CWininetHttp::CWininetHttp(void):m_hSession(NULL),m_hConnect(NULL),m_hRequest(NULL){}CWininetHttp::~CWininetHttp(void){Release();}// 通过HTTP请求：Get或Post方式获取JSON信息 [3/14//shike]const std::string CWininetHttp::RequestJsonInfo(const std::string& lpUrl,HttpRequest type/* = Hr_Get*/,std::string strHeader/*=""*/,std::string strPostData/*=""*/){std::string strRet = "";try{if ( lpUrl.empty()){throw Hir_ParamErr;}Release();m_hSession = InternetOpen(_T("Http-connect"), INTERNET_OPEN_TYPE_PRECONFIG, NULL, NULL, NULL); //局部if ( NULL == m_hSession ){throw Hir_InitErr;}INTERNET_PORT port = INTERNET_DEFAULT_HTTP_PORT;std::string strHostName = "";std::string strPageName = "";ParseURLWeb(lpUrl, strHostName, strPageName, port);printf("lpUrl:%s,\nstrHostName:%s,\nstrPageName:%s,\nport:%d\n",lpUrl.c_str(),strHostName.c_str(),strPageName.c_str(),(int)port);m_hConnect = InternetConnectA(m_hSession, strHostName.c_str(), port, NULL, NULL, INTERNET_SERVICE_HTTP, NULL, NULL);if ( NULL == m_hConnect ){throw Hir_ConnectErr;}std::string strRequestType;if ( Hr_Get == type ){strRequestType = "GET";}else{strRequestType = "POST";}m_hRequest = HttpOpenRequestA(m_hConnect,strRequestType.c_str(), strPageName.c_str(),"HTTP/1.1", NULL, NULL, INTERNET_FLAG_RELOAD, NULL);if ( NULL == m_hRequest ){throw Hir_InitErr;}DWORD dwHeaderSize = (strHeader.empty()) ? 0 : strlen(strHeader.c_str());BOOL bRet = FALSE;if ( Hr_Get == type ){bRet = HttpSendRequestA(m_hRequest,strHeader.c_str(),dwHeaderSize,NULL, 0);}else{DWORD dwSize = (strPostData.empty()) ? 0 : strlen(strPostData.c_str());bRet = HttpSendRequestA(m_hRequest,strHeader.c_str(),dwHeaderSize,(LPVOID)strPostData.c_str(), dwSize);}if ( !bRet ){throw Hir_SendErr;}char szBuffer[READ_BUFFER_SIZE + 1] = {0};DWORD dwReadSize = READ_BUFFER_SIZE;if ( !HttpQueryInfoA(m_hRequest, HTTP_QUERY_RAW_HEADERS, szBuffer, &dwReadSize, NULL) ){throw Hir_QueryErr;}if ( NULL != strstr(szBuffer, "404") ){throw Hir_404;}while( true ){bRet = InternetReadFile(m_hRequest, szBuffer, READ_BUFFER_SIZE, &dwReadSize);if ( !bRet || (0 == dwReadSize) ){break;}szBuffer[dwReadSize]='\0';strRet.append(szBuffer);}}catch(HttpInterfaceError error){m_error = error;}return std::move(strRet);}// 解析Json数据 [11/8//shike]void CWininetHttp::ParseJsonInfo(const std::string &strJsonInfo){Json::Reader reader;//解析json用Json::ReaderJson::Value value;//可以代表任意类型if (!reader.parse(strJsonInfo, value)) {CVLog.LogMessage(LOG_LEVEL_ERROR,"[CXLDbDataMgr::GetVideoGisData] Video Gis parse data error...");}if (!value["result"].isNull()) {int nSize = value["result"].size();for(int nPos = 0; nPos < nSize; ++nPos)//对数据数组进行遍历{//PGCARDDEVDATA stru ;//stru.strCardName = value["result"][nPos]["tollgateName"].asString();//stru.strCardCode = value["result"][nPos]["tollgateCode"].asString();//std::string strCDNum = value["result"][nPos]["laneNumber"].asString(); //增加:车道总数//stru.nLaneNum = atoi(strCDNum.c_str());//std::string strLaneDir = value["result"][nPos]["laneDir"].asString(); //增加:车道方向,进行规则转换//stru.strLaneDir = TransformLaneDir(strLaneDir);//stru.dWgs84_x = value["result"][nPos]["wgs84_x"].asDouble();//stru.dWgs84_y = value["result"][nPos]["wgs84_y"].asDouble();//stru.dMars_x = value["result"][nPos]["mars_x"].asDouble();//stru.dMars_y = value["result"][nPos]["mars_y"].asDouble();//lstCardDevData.emplace_back(stru);}}}// 解析URL地址 [3/14//shike]void CWininetHttp::ParseURLWeb( std::string strUrl, std::string& strHostName, std::string& strPageName, WORD& sPort){sPort = 80;string strTemp(strUrl);std::size_t nPos = strTemp.find("http://");if (nPos != std::string::npos){strTemp = strTemp.substr(nPos + 7, strTemp.size() - nPos - 7);}nPos = strTemp.find('/');if ( nPos == std::string::npos ) //没有找到{strHostName = strTemp;}else{strHostName = strTemp.substr(0, nPos);}std::size_t nPos1 = strHostName.find(':');if ( nPos1 != std::string::npos ){std::string strPort = strTemp.substr(nPos1 + 1, strHostName.size() - nPos1 - 1);strHostName = strHostName.substr(0, nPos1);sPort = (WORD)atoi(strPort.c_str());}if ( nPos == std::string::npos ){return ;}strPageName = strTemp.substr(nPos, strTemp.size() - nPos);}// 关闭句柄 [3/14//shike]void CWininetHttp::Release(){ReleaseHandle(m_hRequest); ReleaseHandle(m_hConnect); ReleaseHandle(m_hSession);}// 释放句柄 [3/14//shike]void CWininetHttp::ReleaseHandle( HINTERNET& hInternet ){if (hInternet) {InternetCloseHandle(hInternet); hInternet = NULL; }}// UTF-8转为GBK2312 [3/14//shike]char* CWininetHttp::UtfToGbk(const char* utf8){int len = MultiByteToWideChar(CP_UTF8, 0, utf8, -1, NULL, 0);wchar_t* wstr = new wchar_t[len+1];memset(wstr, 0, len+1);MultiByteToWideChar(CP_UTF8, 0, utf8, -1, wstr, len);len = WideCharToMultiByte(CP_ACP, 0, wstr, -1, NULL, 0, NULL, NULL);char* str = new char[len+1];memset(str, 0, len+1);WideCharToMultiByte(CP_ACP, 0, wstr, -1, str, len, NULL, NULL);if(wstr) delete[] wstr;return str;}
