未捕獲的ReferenceError：未在DataTable上定義$

Question

所以我在控制台上看到一個錯誤，說

Uncaught ReferenceError: $ is not defined
    at 2e9ecdab-e88c-11e8-95f0-02fba84c29d0:1934

當我深入研究代碼時，問題出在以下代碼中：

$('#cashFlow').DataTable({ //ReferenceError: $ is not defined 
dom: 'Bfrtip',
buttons: [
  {
    extend: 'excel',
    text: 'Export to Excel',
    className: 'btn btn-default',
    exportOptions: {
      columns: 'th:not(:last-child)'
    }
  }],
'paging'      : true,
'searching'   : true,
'ordering'    : true,
"columns" : [
  {"width" : "5%"},
  {"width" : "10%"},
  {"width" : "25%"},
  {"width" : "5%"},
  {"width" : "15%"},
  {"width" : "3%"},
  {"width" : "15%"},
  {"width" : "2%"}
]});

$('#cashFlow')表存在，並且已經在此代碼之上。

<table id="cashFlow" class="table table-striped table-bordered">
<thead>
<tr>
  // ...
  <th>{{__('grabLog.action')}}</th>
</tr>
</thead>
@if(isset($cashflow))
  @foreach($cashflow as $index=>$f)
    <tr>
      // ...
      <td>
        <button class="btn btn-danger btn-cf-delete" bank_account_id="{{$f->bank_account_id}}"
                trans_date="{{$f->trans_date}}"
                description="{{$f->description}}" cab="{{$f->cab}}" amount="{{$f->amount}}"
                type="{{$f->type}}" balance="{{$f->balance}}" skey="{{$skey}}"><i class="fa fa-trash"></i>
        </button>
      </td>
    </tr>
  @endforeach
@endif

我已經在該論壇中搜索了這個問題，所有這些人都回答了應該將jquery.min.js 。 我已經做到了，但是仍然有同樣的問題。

<script src="{{asset('AdminLte/js')}}/jquery/dist/jquery.min.js"></script>
<script src="{{asset('AdminLte/js')}}/jquery/jquery-3.3.1.js"></script>
<script src="{{asset('AdminLte/js')}}/bootstrap/bootstrap.min.js"></script>
<script src="{{asset('AdminLte/js')}}/datatables.net/jquery.dataTables.min.js"></script>
<script src="{{asset('AdminLte/js')}}/datatables.net-bs/dataTables.bootstrap.min.js"></script>
<script src="{{asset('AdminLte/js')}}/datatables.net/dataTables.buttons.min.js"></script>
<script src="{{asset('AdminLte/js')}}/datatables.net/buttons.flash.min.js"></script>
<script src="{{asset('AdminLte/js')}}/ajax/jszip.min.js"></script>
<script src="{{asset('AdminLte/js')}}/ajax/pdfmake.min.js"></script>
<script src="{{asset('AdminLte/js')}}/ajax/vfs_fonts.js"></script>
<script src="{{asset('AdminLte/js')}}/datatables.net/buttons.html5.min.js"></script>
<script src="{{asset('AdminLte/js')}}/datatables.net/buttons.print.min.js"></script>
<script src="{{asset('AdminLte/js')}}/jquery-slimscroll/jquery.slimscroll.min.js"></script>
//there's another javascripts I put in here but didn't show to you because it doesn't related with this question.
<script>
  $.ajaxSetup({
    headers: {
      'X-CSRF-TOKEN': $('meta[name="csrf-token"]').attr('content')
    }
  });
</script>

Answer 1

您需要在頁面底部加載腳本-防止阻止HTML的加載/呈現。

請注意，唯一應該放在頭部的js函數是呈現內容所直接需要的那些js函數，例如對數據源API的調用。 所有頁面內功能應在頁面HTML / CSS之后加載。

然后將jquery函數包裝在$(document).ready({})包裝器中，以確保DOM准備與這些函數進行交互。

樣本頁面結構

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
  <link rel="shortcut icon" href="favicon.ico">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <link rel="stylesheet" href="/css/bootstrap.min.css">
  <link rel="stylesheet" href="/css/font-awesome.min.css">
</head>

<body>
  <script src="/js/jquery.min.js"></script>
  <script src="/js/bootstrap.min.js"></script>
  <script>

  $(document).ready(function(){
  .... put code here ...
  })
 </script>
</body>
</html>