Php Ajax调用中的TypeError

我在Laravel 5中的Ajax调用中遇到以下错误：

TypeError：对未实现接口HTMLInputElement的对象调用了“Stepp”

d=[]，e=函数（a，b）{b=n.isFunction（b）？b（）：null==b？”：b

表格如下：

<form id="comment_form">
    <input type="textarea" class="form-control_comment" id="comment" placeholder="Type your comment here...">
    <input type="hidden" name="uid" id="uid" value="{{$user->id}}">
    <input type="hidden" name="pid" id="pid" value="{{$post->id}}">
    <input type="hidden" id="token" value="{{$csrf_token()}}">
    <button type="button" class="btn btn-sm btn-success" id= "comment_button">Submit</button>
</form>

以及后置控制器中的操作部分：

 public function postComment_action()
{

    if(Auth::check())
    {
        if(Request::ajax())
        {
            $inputs= Input::all();

        }

        $new_comment= $inputs['newComment'];
        $uid= $inputs['uid'];
        $pid= $inputs['pid'];
        $com= new Comment;
        $com->content= $new_comment;
        $com->userId= $uid;
        $com->postId= $pid;
        $com->save();

        $data= array();

        $all_comments= Comment::where('postId', $pid)->first();
        $u= User::where('id', $uid);

        foreach($all_comments as $coms)
        {
            $data= $coms->content;
        }

        $data= json_encode($data);
        echo $data;
    }
    else
    {
        return Redirect::route('signin_user')->withErrors("You must sign in to perform this action");
    }

}

任何帮助都将不胜感激：）

Route::post('post/comment_action', array('as'=>'post/comment_action', 'uses'=>'PostController@postComment_action'));

 public function postComment_action()
{

    if(Auth::check())
    {
        if(Request::ajax())
        {
            $inputs= Input::all();

        }

        $new_comment= $inputs['newComment'];
        $uid= $inputs['uid'];
        $pid= $inputs['pid'];
        $com= new Comment;
        $com->content= $new_comment;
        $com->userId= $uid;
        $com->postId= $pid;
        $com->save();

        $data= array();

        $all_comments= Comment::where('postId', $pid)->first();
        $u= User::where('id', $uid);

        foreach($all_comments as $coms)
        {
            $data= $coms->content;
        }

        $data= json_encode($data);
        echo $data;
    }
    else
    {
        return Redirect::route('signin_user')->withErrors("You must sign in to perform this action");
    }

}