libcurl第三課 HTTP獲取天氣信息

場景說明
       從 t.weather.sojson.com網頁中獲取天氣信息。若是不使用libcurl庫，須要實現Transfer-Encoding: chunked分塊接收和Content-Encoding: gzip解壓，如今提供libcurl實現代碼

代碼
size_t WriteResponseBody(void *ptr, size_t size, size_t nmemb, void *userData)
{
 std::string* pStrBuffer = (std::string*)userData;
 size_t nLen = size * nmemb;
 pStrBuffer->append((char*)ptr, nLen);
 return nLen;
}
int GetWeatherUsingCurl(const std::string &strUrl, std::string& strResponseData)
{
 CURL *pCurlHandle = curl_easy_init();
 curl_easy_setopt(pCurlHandle, CURLOPT_CUSTOMREQUEST, "GET");
 curl_easy_setopt(pCurlHandle, CURLOPT_URL, strUrl.c_str());
 curl_easy_setopt(pCurlHandle, CURLOPT_WRITEFUNCTION, WriteResponseBody);//設置回調函數
 //curl_easy_setopt(pCurlHandle, CURLOPT_HEADER, 1);//保存HTTP頭部信息到strResponseData
 curl_easy_setopt(pCurlHandle, CURLOPT_WRITEDATA, &strResponseData);//設置回調函數的參數,獲取反饋信息
 curl_easy_setopt(pCurlHandle, CURLOPT_TIMEOUT, 15);//接收數據時超時設置，若是10秒內數據未接收完，直接退出
 curl_easy_setopt(pCurlHandle, CURLOPT_MAXREDIRS, 1);//查找次數，防止查找太深
 curl_easy_setopt(pCurlHandle, CURLOPT_CONNECTTIMEOUT, 5);//鏈接超時，這個數值若是設置過短可能致使數據請求不到就斷開了
 CURLcode nRet = curl_easy_perform(pCurlHandle);
 curl_easy_cleanup(pCurlHandle);
 return nRet;
}

調用例子
 std::string strResponseData;
 GetWeatherUsingCurl("t.weather.sojson.com/api/weather/city/101200101", strResponseData);