public static function curl($url, $params = false, $ispost = 0, $https = 0)
    {
        $httpInfo = array();
        $ch = curl_init();
        curl_setopt($ch, CURLOPT_HTTP_VERSION, CURL_HTTP_VERSION_1_1);
        curl_setopt($ch, CURLOPT_USERAGENT, 'Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/41.0.2272.118 Safari/537.36');
        curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, 30);
        curl_setopt($ch, CURLOPT_TIMEOUT, 30);
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
        if ($https) {
            curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, FALSE); // 对认证证书来源的检查
            curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, FALSE); // 从证书中检查SSL加密算法是否存在
        }
        if ($ispost) {
            curl_setopt($ch, CURLOPT_POST, true);
            curl_setopt($ch, CURLOPT_POSTFIELDS, $params);
            curl_setopt($ch, CURLOPT_URL, $url);
        } else {
            if ($params) {
                if (is_array($params)) {
                    $params = http_build_query($params);
                }
　　　　　　
                curl_setopt($ch, CURLOPT_URL, $url . '?' . $params);　　// 此处就是参数的列表,给你加了个?
            } else {
                curl_setopt($ch, CURLOPT_URL, $url);
            }
        }

        $response = curl_exec($ch);

        if ($response === FALSE) {
            //echo "cURL Error: " . curl_error($ch);
            return false;
        }
        $httpCode = curl_getinfo($ch, CURLINFO_HTTP_CODE);
        $httpInfo = array_merge($httpInfo, curl_getinfo($ch));
        curl_close($ch);
        return $response;
    }



// 发送请求 
$result = self::curl('网址', '参数', true); 
// 收到的数据需要转化一下
$json = json_decode($result);

我的用法是,应为我调用的是天气预报的接口

$result= Curl::curl($url,"city=北京");