C++实现HTTP POST GET请求

最近写网络验证要用到，而且功能较简单，所以找了这么一段代码，没有去用那些常用的网络请求库。

WininetHttp.h

#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        4096

enum 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URL
	Hir_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 [3/14/2017/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 [3/14/2017/shike]
	//void ParseJsonInfo(const std::string& strJsonInfo);

	// 关闭句柄 [3/14/2017/shike]
	void Release();

	// 释放句柄 [3/14/2017/shike]
	void ReleaseHandle(HINTERNET& hInternet);

	// 解析URL地址 [3/14/2017/shike]
	void ParseURLWeb(std::string strUrl, std::string& strHostName, std::string& strPageName, WORD& sPort);

	// UTF-8转为GBK2312 [3/14/2017/shike]
	char* UtfToGbk(const char* utf8);

private:
	HINTERNET            m_hSession;
	HINTERNET            m_hConnect;
	HINTERNET            m_hRequest;
	HttpInterfaceError    m_error;
};

WininetHttp.cpp

/*************************************************
File name  :  WininetHttp.cpp
Description:  通过URL访问HTTP请求方式获取JSON
Author     :  shike
Version    :  1.0
Date       :  2016/10/27
Copyright (C) 2016 -  All Rights Reserved
*************************************************/
#include "WininetHttp.h"

#include <iostream>

#include <fstream>

#pragma comment(lib, "Wininet.lib")
#include <tchar.h>
using namespace std;



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 [3/14/2017/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URL地址 [3/14/2017/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 [3/14/2017/shike]
void CWininetHttp::Release()
{
	ReleaseHandle(m_hRequest);
	ReleaseHandle(m_hConnect);
	ReleaseHandle(m_hSession);
}

// 释放句柄 [3/14/2017/shike]
void CWininetHttp::ReleaseHandle(HINTERNET& hInternet)
{
	if (hInternet)
	{
		InternetCloseHandle(hInternet);
		hInternet = NULL;
	}
}

// UTF-8转为GBK2312 [3/14/2017/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;
}

使用

string dats = request.RequestJsonInfo("http://evrstr.cc/", Hr_Get);