php curl 无法post怎么办

function http_req($http_type, $method, $url, $data)
{
    $ch = curl_init();
    if (strstr($http_type, 'https')) {
        curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
        curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 0);
    }

    if ($method == 'post') {
        curl_setopt($ch, CURLOPT_POST, 1);
        curl_setopt($ch, CURLOPT_POSTFIELDS, $data);
    } else {
        $url = $url . '?' . $data;
    }
    curl_setopt($ch, CURLOPT_URL, $url);
    curl_setopt($ch, CURLOPT_HEADER, 0);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
    curl_setopt($ch, CURLOPT_TIMEOUT, 100000);//超时时间

    try {
        $ret = curl_exec($ch);
    } catch (Exception $e) {
        curl_close($ch);
        return json_encode(array('ret' => 0, 'msg' => 'failure'));
    }
    curl_close($ch);
    return $ret;
}
  //第一种提交方式在遇到post_data 中包含@等一些符号时会出现提交失败的情况
  $url = "http://localhost/web_services.php";
　$post_data = array ("username" => "bob","key" => "12345");
　$response = http_req('http', 'post', $url, $post_data );
　//第二种提交方式可以避免
　$url = "http://localhost/web_services.php";
　$post_data = "username=bob&key=12345";
　$response = http_req('http', 'post', $url, $post_data );

  　

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