我正在尝试使用laravel和ajax在db中插入一行，而不刷新页面，但是当我单击submit按钮时，在浏览器控制台响应中收到以下错误：

SQLSTATE[23000]: Integrity constraint violation: 1048 Column 'writer_id2' cannot be null.

我猜，输入数据还没有提交，值是空的，但是我如何在控制器中接收响应/输入数据并同时将其插入数据库？
路线：

Route::post('writers', ['as'=>'add-writer' ,'uses'=> 'HomeController@addWriter'])->name('add-writer');

控制器：

public function addWriter(){
  $i = new Input();
  $dm=  new DataModel();
  $data= response()->json(['data'=>$i::all()]);
  $encode = json_encode($data);
  $decode = json_decode($encode,true);
  $decoded = [];
  $decodedNeeded = [];
  $inc = 0;
  $i2 = 0;

  foreach ($decode as $k=>$v){
      $inc++;
      $decoded[$inc] = $v;

  }
  foreach($decoded[2] as $k3 =>$v3){
      $i2++;
       $decodedNeeded[$i2] = $v3;
  }

  $this->insertUser = $decodedNeeded;

 $dm->addWriterMethod($decodedNeeded[1]['writer_id2'],$decodedNeeded[1]['status'],$decodedNeeded[1]['writer-skills']);

ajax

$('#add-writer-btn').click(function(e) {
   e.preventDefault();
     var id = $('input[name=writer_id2]').val();
     var status = $("input[name=status]").val();
     var skills = $('textarea').val();

     var form2 = $(this);
     var url2 = form2.attr('action');

     $.ajax({
         headers: {'X-CSRF-TOKEN': $('meta[name="csrf-token"]').attr('content')},
         method: "POST",
         ContentType: 'application/json',
         url: url2,
         dataType: 'json',

         data: {

             'id': id,
             'status': status,
             'skills': skills

         },

         success: function (data) {
           alert('Added successfully!');
         }

     });

 });

html格式

<div id="add-writer">
               <b>Add writer</b>

                       <form action="{{url('add-writer')}}" method="POST">    
                  <input type="hidden" name="_token" value="{{csrf_token()}}">

             Writer_id2 <input type="number" id="writer-id-2" name="writer_id2">
                  <br>
               Open to suggestions   <input type="radio" value="Open to suggestions"  name="status">
                  <br>
                 Searching for orders  <input type="radio" value="Searching for orders"  name="status">

                  <br><br>
                  Writer skills <textarea   name="writer-skills"></textarea>

                  <input type="submit" value="Add" id="add-writer-btn" >

                       </form>

          </div>