Simple HTTP Client using WININET

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Introduction

This class is used for HTTP REQUEST. It supports HTTP GET, HTTP POST and HTTP POST-MultiPartFormData.

Class Overview

class GenericHTTPClient {
public:                    
    ...
    // CONSTRUCTOR & DESTRUCTOR
    GenericHTTPClient();
    virtual ~GenericHTTPClient();

    ...
    // Connection handler    
    BOOL Connect(    LPCTSTR szAddress,
            LPCTSTR szAgent = __DEFAULT_AGENT_NAME,
            unsigned short nPort = INTERNET_DEFAULT_HTTP_PORT,
            LPCTSTR szUserAccount = NULL,
            LPCTSTR szPassword = NULL);

    BOOL Close();
    VOID InitilizePostArguments();

    // HTTP Arguments handler    
    VOID AddPostArguments(LPCTSTR szName, DWORD nValue);
    VOID AddPostArguments(LPCTSTR szName, LPCTSTR szValue, 
      BOOL bBinary = FALSE);

    // HTTP Method handler 
    BOOL Request(    LPCTSTR szURL,
            int nMethod = GenericHTTPClient::RequestGetMethod,
            LPCTSTR szAgent = __DEFAULT_AGENT_NAME);

    BOOL RequestOfURI(LPCTSTR szURI, int nMethod = 
           GenericHTTPClient::RequestGetMethod);
    BOOL Response(PBYTE pHeaderBuffer, DWORD dwHeaderBufferLength, 
           PBYTE pBuffer, DWORD dwBufferLength, DWORD &dwResultSize);    
    LPCTSTR QueryHTTPResponse();
    LPCTSTR QueryHTTPResponseHeader();    

    // General Handler
    DWORD GetLastError();
    LPCTSTR GetContentType(LPCTSTR szName);
    VOID ParseURL(LPCTSTR szURL, LPTSTR szProtocol, LPTSTR szAddress, 
          DWORD &dwPort, LPTSTR szURI);
    
protected:                
    ...
};

• Connect(...) method connects to HTTP Server.
• Close() method closes connection. These are used with RequestOfURI(...).
• InitilizePostArguments() method initializes post arguments.
• AddPostArguments(...) method is supported so that you can add new post arguments of the following 3 types ( TCHAR, DWORD, FILE).
• Request(...) method is for you to attempt request for HTTP REQUEST( GET, POST, POST-MULTIPARTFORMDATA) with URL. HTTP METHOD indirector have 3 types.
  • GenericHTTPClient::GetMethod is HTTP GET REQUEST
  • GenericHTTPClient::PostMethod is HTTP POST REQUEST
  • GenericHTTPClient::PostMultiPartsFormData is HTTP POST REQUEST with BINARY FORM DATA
• RequestOfURI(...) method is that you could have attempt request for HTTP REQUEST with URI. This method is used with Connect(...) and Close().
• Response(...) method is that you have HTTP Response by BYTES.
• QueryHTTPResponse() method is you have receive HTML of your HTTP REQUEST.
• QueryHTTPResponseHeader() method is you have receive HTTP HEADER about QueryHTTPResponse().
• GetLastError() method is you get windows error code.
• GetContentType(...) method is you have get MIME-TYPE.
• ParseURL(...) method parse URL to protocol(HTTP, HTTPS) and address(or hostname) and port, URI.

Usage

Now, you have to simply do  HTTP GET REQUEST iteration.

....

GenericHTTPClient    httpClient;

if(httpRequest.Request("http://www.codeproject.com")){
    LPCTSTR szHTML=httpRequest.QueryResponse();
}else{
    LPVOID     lpMsgBuffer;
    DWORD dwRet=FormatMessage( FORMAT_MESSAGE_ALLOCATE_BUFFER | 
             FORMAT_MESSAGE_FROM_SYSTEM,
             NULL,
             httpRequest.GetLastError(),
             MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
             reinterpret_cast<LPTSTR>(&lpMsgBuffer),
             0,
             NULL);                         

    MessageBox( reinterpret_cast<LPTSTR>(lpMsgBuffer), "ERROR", MB_OK);
    LocalFree(lpMsgBuffer);
}

This is HTTP POST REQUEST with file posting ( HTTP POST Multipart/form-data)

GenericHTTPClient *pClient=new GenericHTTPClient();

    pClient->InitilizePostArguments();
    pClient->AddPostArguments(__TAG_USRID, szUserID);
    pClient->AddPostArguments(__TAG_JUMIN, szSocialIndex);
    pClient->AddPostArguments(__TAG_SRC, szSource);
    pClient->AddPostArguments(__TAG_DST, szDestination);            
    pClient->AddPostArguments(__TAG_FORMAT, szFormat);
    pClient->AddPostArguments(__TAG_SUBJECT, szMessage);

    if(bCharge){
        pClient->AddPostArguments(__TAG_CHARGE, "Y");
    }else{
        pClient->AddPostArguments(__TAG_CHARGE, "N");
    }
    pClient->AddPostArguments(__TAG_CPCODE, szCPCode);
    pClient->AddPostArguments(__TAG_FILE, szFile, TRUE);

    if(pClient->Request(szURL, 
        GenericHTTPClient::RequestPostMethodMultiPartsFormData)){        
        LPCTSTR szResult=pClient->QueryHTTPResponse();
    }else{
#ifdef    _DEBUG
        LPVOID     lpMsgBuffer;
        DWORD dwRet=FormatMessage( FORMAT_MESSAGE_ALLOCATE_BUFFER |
                      FORMAT_MESSAGE_FROM_SYSTEM,
                      NULL,
                      pClient->GetLastError(),
                      MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
                      reinterpret_cast<LPTSTR>(&lpMsgBuffer),
                      0,
                      NULL);
        OutputDebugString(reinterpret_cast<LPTSTR>(lpMsgBuffer));
        LocalFree(lpMsgBuffer);
#endif
    }

}

Thanks

Thanks that you have been reading my article and my bad English. ;p