Libevent::evhttp服务器下载

void http_handler_Get_Download(struct evhttp_request *req, void *arg){ ???if (req == NULL) ???{ ???????return; ???} ???const char *uri = evhttp_request_get_uri(req); ???string strUrl(uri); ???string strFilePath = DPC::get_Url_path(strUrl, "path="); ???printf("FilePath = %s \n", strFilePath.c_str()); ???string strFileName = DPC::get_FileName_path(strUrl, "/"); ???strFileName = "attachment; filename=" + strFileName; ???//查看文件是否存在 ???if (access(strFilePath.c_str(), 0) == -1) ???{ ???????evhttp_send_error(req, HTTP_BADREQUEST, 0); ???????return; ???} ???//========= ???std::ifstream t; ???t.open(strFilePath.c_str(), ios::in | ios::binary); ???t.seekg(0, std::ios::end); ???long length = t.tellg(); ???t.seekg(0, std::ios::beg); ???char *buffer = new char[length]; ???t.read(buffer, length); ???t.close(); ???char FileSize[10] = { ‘\0‘ }; ???snprintf(FileSize, sizeof(FileSize), "%d", length); ???time_t timep; ???time(&timep); ???char s[50]; ???sprintf(s, ctime(&timep)); ???std::string strDate = std::string(s, s + (strlen(s) - 1)); ???evhttp_add_header(evhttp_request_get_output_headers(req), "Server", "Unix"); ???evhttp_add_header(evhttp_request_get_output_headers(req), "Content-Type", "application/octet-stream; charset=utf-8"); ???evhttp_add_header(evhttp_request_get_output_headers(req), "Content-Disposition", strFileName.c_str()); ???evhttp_add_header(evhttp_request_get_output_headers(req), "Content-Length", FileSize); ???evhttp_add_header(evhttp_request_get_output_headers(req), "Date", strDate.c_str()); ???evhttp_add_header(evhttp_request_get_output_headers(req), "Connection", "close"); ???//========= ???//回响应 ???struct evbuffer *retbuff = NULL; ???retbuff = evbuffer_new(); ???if (retbuff == NULL) ???{ ???????return; ???} ???evbuffer_add(retbuff, buffer, length); ???//evbuffer_add_printf(retbuff, "123"); ???evhttp_send_reply(req, HTTP_OK, "Client", retbuff); ???evbuffer_free(retbuff);}