sendClond如何更新邮件模板

        $url = 'http://www.sendcloud.net/webapi/template.update.json';

        $API_USER = '';
        $API_KEY = '';

        $content = "hello  world";//需要替换的html内容

        $param = array(
            'api_user' => $API_USER, # 使用api_user和api_key进行验证
            'api_key' => $API_KEY,
            'invoke_name' => 'talk',
            'html'   => $content,
        );


        $data = http_build_query($param);

        $options = array(
            'http' => array(
                'method' => 'POST',
                'header' => 'Content-Type: application/x-www-form-urlencoded',
                'content' => $data
        ));
        $context  = stream_context_create($options);
        $result = file_get_contents($url, FILE_TEXT, $context);
        echo $result;

之前使用curl方法一直报错,这个才是对的