Question

在下面的代码中，我试图从远程服务器上的php脚本获取数据，以响应变量中的post请求。

我花了这么多时间找到bug，但是不能，这是在非oop环境中完美运行的相同代码。但现在它返回所有类型的错误数据，返回的数据（std :: string）是虽然持久，但对于一组发布的数据，返回的数据（std :: string）总是相同的。

我用html格式检查了脚本，没有问题。所以我猜我写代码有问题。

我在OOP环境中使用C ++和libCurl。

#include "Server.h"



namespace model
{

// private:

Server::Server (  ) 
{  

   curl_global_init ( CURL_GLOBAL_ALL );
   curl = curl_easy_init (  ) ;

};



Server* Server::singleton = NULL;


// public:

Server* Server::Instance (  )
{

    if ( !singleton ) singleton = new Server ( );

    return singleton;

};



Server::~Server ( ) 
{

   curl_easy_cleanup ( curl );
   curl_global_cleanup ( );

};



std::string Server::readScript ( std::string scriptAddress, std::string postData )
{

    std::string response = "-1";


    if ( curl ) 
    {

        curl_easy_setopt (  curl, CURLOPT_URL, scriptAddress.c_str (  )  );

        curl_easy_setopt ( curl, CURLOPT_WRITEFUNCTION, &Server::writeString );
        curl_easy_setopt ( curl, CURLOPT_WRITEDATA, &response );


        if (  ! postData.empty (  )  )
        {

            curl_easy_setopt (  curl, CURLOPT_POSTFIELDS, postData.c_str (  )  );

        }


        curl_easy_setopt ( curl, CURLOPT_CONNECTTIMEOUT, 10L );

        CURLcode cc = curl_easy_perform ( curl );


        if (  cc == CURLE_OPERATION_TIMEDOUT  ) MessageBox ( 0, "The operation timed out.\nPlease try again later.", "Error!", MB_OK | MB_ICONEXCLAMATION );

        else if (  cc == CURLE_COULDNT_CONNECT  )   MessageBox ( 0, "Couldn't conect to the server.\nPlease try again later.", "Error!", MB_OK | MB_ICONEXCLAMATION );

        else if (  cc == CURLE_REMOTE_ACCESS_DENIED  )  MessageBox ( 0, "Access is denied.\nPlease contact our support team.", "Error!", MB_OK | MB_ICONEXCLAMATION );

        else if (  cc == CURLE_GOT_NOTHING  )   MessageBox ( 0, "Server did not return anything.\nPlease try again later, if the problem persist please contact our support team.", "Error!", MB_OK | MB_ICONEXCLAMATION );

        else if (  cc == CURLE_REMOTE_FILE_NOT_FOUND  ) MessageBox ( 0, "Couldn't find resource.\nPlease try again later, if the problem persist please contact our support team.", "Error!", MB_OK | MB_ICONEXCLAMATION );

        else if (  cc == CURLE_FAILED_INIT  )   MessageBox ( 0, "The initialization failed.\nPlease contact our support team.", "Error!", MB_OK | MB_ICONEXCLAMATION );

        else if (  cc == CURLE_COULDNT_RESOLVE_HOST  )  MessageBox ( 0, "Couldn't resolve host.\nPlease contact our support team.", "Error!", MB_OK | MB_ICONEXCLAMATION );

        else if (  cc == CURLE_WRITE_ERROR  )   MessageBox ( 0, "Response write error.\nPlease contact our support team.", "Error!", MB_OK | MB_ICONEXCLAMATION );

        else if (  cc == CURLE_TOO_MANY_REDIRECTS  )    MessageBox ( 0, "Droping connection, due to too many redirects.\nPlease contact our support team.", "Error!", MB_OK | MB_ICONEXCLAMATION );

        else if (  cc == CURLE_SEND_ERROR  )    MessageBox ( 0, "Failed sending data to the server.\nPlease try again later, if the problem persist please contact our support team.", "Error!", MB_OK | MB_ICONEXCLAMATION );

        else if (  cc == CURLE_REMOTE_FILE_NOT_FOUND  ) MessageBox ( 0, "Remote server could not be found.\nPlease try again later, if the problem persist please contact our support team.", "Error!", MB_OK | MB_ICONEXCLAMATION );

        MessageBox( 0, response.c_str(), "response", 0 );

    }

    else
    {

        MessageBox ( 0, "Something went wrong.\nPlease try again later.", "Error!", MB_OK | MB_ICONEXCLAMATION );

    }


    return response;

};





/**     private static function     */
/** -------------------------------------------------------------------------------------------------------------------------------- */
/** -------------------------------------------------------------------------------------------------------------------------------- */


int Server::writeString ( void *ptr, int size, int count, void *stream ) 
{


  ( ( std::string* ) stream )->append (  ( char* ) ptr, 0, size*count  );


  return size*count;


}


};// end of namespace model

修改当我期待 0 时，它会返回 -10 ，当 3 时，它会返回 -13 ，当 1 预计会返回 -11 ，依此类推。

Answer 1

也许你的追加位置是错误的。

替换你的写功能

((std::string*)stream)->append((char*)ptr,0,size*count);

遵循代码。

((std::string* )stream)->append((char*)ptr);

Answer 2

这样的傻瓜，我正在初始化std :: string response =“ - 1”;所以Server :: writeString中的每个“append”都将结果附加在“-1”的末尾。需要确保如果服务器有响应，请先清除std :: string。

libCurl写入函数中无法检测到错误

2 个答案: