求助钉钉的媒体文件上传好复杂啊

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    function posthttps($url, $data,$header, $info=true) {
        $ch = curl_init ();
        $res = curl_setopt ( $ch, CURLOPT_URL, $url );
        curl_setopt ( $ch, CURLOPT_SSL_VERIFYHOST, FALSE );
        curl_setopt ( $ch, CURLOPT_SSL_VERIFYPEER, FALSE );
        curl_setopt ( $ch, CURLOPT_HEADER, 0 );
        curl_setopt ( $ch, CURLOPT_POST, 1 );
        curl_setopt ( $ch, CURLOPT_POSTFIELDS, $data );
        curl_setopt ( $ch, CURLOPT_RETURNTRANSFER, 1 );
        curl_setopt ( $ch, CURLOPT_HTTPHEADER, $header );
        $result = curl_exec ( $ch );
        curl_close($ch);
        return json_decode ( $result,$info );
    }
    $header=array('Content-Type: multipart/form-data');
header这样写就提示：{"errcode":43008,"errmsg":"参数需要multipart类型"}

$header=array('Content-Type:application/json');
这样写就提示：{"errcode":40035,"errmsg":"不合法的参数"}

$data参数和$header到底要怎样的格式才对