C++调用HTTP实现方式

来源：互联网发布：palantir 知乎编辑：程序博客网时间：2024/05/27 18:17

Http访问有两种方式，GET和POST，就编程来说GET方式相对简单点，它不用向服务器提交数据，程序中使用POST方式，
提交数据并从服务器获取返回值。

为实现Http访问，微软提供了二套API：WinINet, WinHTTP。WinHTTP比WinINet更加安全和健壮，可以这么认为WinHTTP是WinINet的升级版本。
程序中，通过一个宏的设置来决定是使用WinHttp还是WinINet。

#define USE_WINHTTP //Comment this line to user wininet.

下面来说说实现Http访问的流程（两套API都一样的流程）：

1，首先我们打开一个Session获得一个HINTERNET session句柄；

2，然后我们使用这个session句柄与服务器连接得到一个HINTERNET connect句柄；

3，然后我们使用这个connect句柄来打开Http 请求得到一个HINTERNET request句柄；

4，这时我们就可以使用这个request句柄来发送数据与读取从服务器返回的数据；

5，最后依次关闭request，connect，session句柄。

/***********************定义HTTP发送所用方法***********************************/HINTERNET OpenSession(LPCWSTR userAgent = 0){#ifdef USE_WINHTTP    return WinHttpOpen(userAgent, NULL, NULL, NULL, NULL);;#else    return InternetOpen(userAgent, INTERNET_OPEN_TYPE_PRECONFIG, NULL, NULL, 0);#endif}HINTERNET Connect(HINTERNET hSession, LPCWSTR serverAddr, int portNo){#ifdef USE_WINHTTP    return WinHttpConnect(hSession, serverAddr, (INTERNET_PORT) portNo, 0);#else    return InternetConnect(hSession, serverAddr, portNo, NULL, NULL, INTERNET_SERVICE_HTTP, 0, 0);#endif}HINTERNET OpenRequest(HINTERNET hConnect, LPCWSTR verb, LPCWSTR objectName, int scheme){    DWORD flags = 0;#ifdef USE_WINHTTP    if (scheme == INTERNET_SCHEME_HTTPS) {        flags |= WINHTTP_FLAG_SECURE;    }    return WinHttpOpenRequest(hConnect, verb, objectName, NULL, NULL, NULL, flags);#else    if (scheme == INTERNET_SCHEME_HTTPS) {        flags |= INTERNET_FLAG_SECURE;    }    return HttpOpenRequest(hConnect, verb, objectName, NULL, NULL, NULL, flags, 0);#endif}BOOL AddRequestHeaders(HINTERNET hRequest, LPCWSTR header){    SIZE_T len = lstrlenW(header);#ifdef USE_WINHTTP    return WinHttpAddRequestHeaders(hRequest, header, DWORD(len), WINHTTP_ADDREQ_FLAG_ADD);#else    return HttpAddRequestHeaders(hRequest, header, DWORD(len), HTTP_ADDREQ_FLAG_ADD);#endif}BOOL SendRequest(HINTERNET hRequest, const void* body, DWORD size){#ifdef USE_WINHTTP    return WinHttpSendRequest(hRequest, 0, 0, const_cast<void*>(body), size, size, 0);#else    return HttpSendRequest(hRequest, 0, 0, const_cast<void*>(body), size);#endif}BOOL EndRequest(HINTERNET hRequest){#ifdef USE_WINHTTP    return WinHttpReceiveResponse(hRequest, 0);#else    // if you use HttpSendRequestEx to send request then use HttpEndRequest in here!    return TRUE;#endif}BOOL QueryInfo(HINTERNET hRequest, int queryId, char* szBuf, DWORD* pdwSize){#ifdef USE_WINHTTP    return WinHttpQueryHeaders(hRequest, (DWORD) queryId, 0, szBuf, pdwSize, 0);#else    return HttpQueryInfo(hRequest, queryId, szBuf, pdwSize, 0);#endif}BOOL ReadData(HINTERNET hRequest, void* buffer, DWORD length, DWORD* cbRead){#ifdef USE_WINHTTP    return WinHttpReadData(hRequest, buffer, length, cbRead);#else    return InternetReadFile(hRequest, buffer, length, cbRead);#endif}void CloseInternetHandle(HINTERNET hInternet){    if (hInternet){#ifdef USE_WINHTTP        WinHttpCloseHandle(hInternet);#else        InternetCloseHandle(hInternet);#endif    }}/**********************************************************////通过Http方式发送短信string SendSMS_HTTP(const long ececcid,const string & password ,const string & msisdn, const string &smsContent){ string rtnStr ="-1";    HINTERNET hSession = 0;    HINTERNET hConnect = 0;    HINTERNET hRequest = 0;    wstring strHeader(L"Content-type: application/x-www-form-urlencoded\r\n");    // Test data    CrackedUrl crackedUrl(L"http://pi.f3.cn/SendSMS.aspx"); string StrPostData = "ececcid=600000&password="+password+"&msisdn="+msisdn+"&smscontent="+smsContent+"&msgtype=5&longcode=";  StrPostData = string_To_UTF8(StrPostData);    // Open session.    hSession = OpenSession(L"HttpPost by lyz_sea@163.com");    if (hSession == NULL) {        cout<<"Error:Open session!\n";        return "-1";    }    // Connect.    hConnect = Connect(hSession, crackedUrl.GetHostName(), crackedUrl.GetPort());    if (hConnect == NULL) {        cout<<"Error:Connect failed!\n";        return "-1";    }    // Open request.    hRequest = OpenRequest(hConnect, L"POST", crackedUrl.GetPath(), crackedUrl.GetScheme());    if (hRequest == NULL) {        cout<<"Error:OpenRequest failed!\n";        return "-1";   }    // Add request header. if (!AddRequestHeaders(hRequest, strHeader.c_str())) {        cout<<"Error:AddRequestHeaders failed!\n";        return "-1";    }    // Send post data. if (!SendRequest(hRequest, StrPostData.c_str(), StrPostData.length())) {        cout<<"Error:SendRequest failed!\n";        return "-1";    }    // End request    if (!EndRequest(hRequest)) {        cout<<"Error:EndRequest failed!\n";        return "-1";    }    char szBuf[BUF_SIZE];    DWORD dwSize = 0;    szBuf[0] = 0;    // Query header info.#ifdef USE_WINHTTP    int contextLengthId = WINHTTP_QUERY_CONTENT_LENGTH;    int statusCodeId = WINHTTP_QUERY_STATUS_CODE;    int statusTextId = WINHTTP_QUERY_STATUS_TEXT;#else    int contextLengthId = HTTP_QUERY_CONTENT_LENGTH;    int statusCodeId = HTTP_QUERY_STATUS_CODE;    int statusTextId = HTTP_QUERY_STATUS_TEXT;#endif    dwSize = BUF_SIZE;    if (QueryInfo(hRequest, contextLengthId, szBuf, &dwSize)) {        szBuf[dwSize] = 0;        cout<<"Content length: "<<szBuf<<endl;    }    dwSize = BUF_SIZE;    if (QueryInfo(hRequest, statusCodeId, szBuf, &dwSize)) {        szBuf[dwSize] = 0;        cout<<"Status code: "<< szBuf<<endl;    }    dwSize = BUF_SIZE;    if (QueryInfo(hRequest, statusTextId, szBuf, &dwSize)) {        szBuf[dwSize] = 0;        cout<<"Status text:"<<szBuf<<endl;    }    // read data.    for (;;) {        dwSize = BUF_SIZE;        if (ReadData(hRequest, szBuf, dwSize, &dwSize) == FALSE) {           break;        }        if (dwSize <= 0) {            break;        }        szBuf[dwSize] = 0;          rtnStr =::UTF8_To_string(string(szBuf));  cout<<rtnStr<<endl;//Output 返回值       }    CloseInternetHandle(hRequest);    CloseInternetHandle(hConnect);    CloseInternetHandle(hSession); return  rtnStr;}  以上方法中用到的CrackURL方法在以下CrackURL.h文件中：#pragma once//#include<iostream>//using namespace std;#define USE_WINHTTP    //Comment this line to user wininet. #ifdef USE_WINHTTP     #include <winhttp.h>     #pragma comment(lib, "winhttp.lib") #else     #include <wininet.h>     #pragma comment(lib, "wininet.lib") #endif // CrackedUrl class CrackedUrl {     int m_scheme;     wstring m_host;     int m_port;     wstring m_path; public:     CrackedUrl(LPCWSTR url)     {         URL_COMPONENTS uc = { 0};         uc.dwStructSize = sizeof(uc);          const DWORD BUF_LEN = 256;          WCHAR host[BUF_LEN];         uc.lpszHostName = host;         uc.dwHostNameLength = BUF_LEN;          WCHAR path[BUF_LEN];         uc.lpszUrlPath = path;         uc.dwUrlPathLength = BUF_LEN;          WCHAR extra[BUF_LEN];         uc.lpszExtraInfo = extra;         uc.dwExtraInfoLength = BUF_LEN;  #ifdef USE_WINHTTP         if (!WinHttpCrackUrl(url, 0, ICU_ESCAPE, &uc)) {             cout<<"Error:WinHttpCrackUrl failed!\n";         }  #else         if (!InternetCrackUrl(url, 0, ICU_ESCAPE, &uc)) {             printf("Error:InternetCrackUrl failed!\n");         } #endif         m_scheme = uc.nScheme;         m_host = host;         m_port = uc.nPort;         m_path = path;     }      int GetScheme() const     {         return m_scheme;     }      LPCWSTR GetHostName() const     {   return m_host.c_str();    }    int GetPort() const     {         return m_port;     }      LPCWSTR GetPath() const     {   return m_path.c_str();     }      static string UrlEncode(const char* p)     {         if (p == 0) {             return string();         }          string buf;         for (;;) {             int ch = (BYTE) (*(p++));             if (ch == '\0') {                 break;             }              if (isalnum(ch) || ch == '_' || ch == '-' || ch == '.') {                 buf += (char)ch;            }            else if (ch == ' ') {                buf += '+';            }            else {                char c[16];                wsprintfA(c, "%%%02X", ch);                buf += c;            }        }        return buf;    }};