Javascript Array Concat 不工作.为什么?

问题描述

所以我创建了这个 jqueryui 小部件.它创建了一个 div，我可以将错误输入其中.小部件代码如下所示:

So I've created this jqueryui widget. Its creates a div that I can stream errors into. The widget code looks like this:

$.widget('ui.miniErrorLog', {
   logStart: "<ul>",   // these next 4 elements are actually a bunch more complicated.
   logEnd:   "</ul>",
   errStart: "<li>",
   errEnd:   "</li>",
   content:  "",
   refs:     [],

   _create: function() { $(this.element).addClass( "ui-state-error" ).hide(); },

   clear: function() {
      this.content = "";
      for ( var i in this.refs )
         $( this.refs[i] ).removeClass( "ui-state-error" );
      this.refs = [];
      $(this.element).empty().hide();
   },

   addError: function( msg, ref ) {
      this.content += this.errStart + msg + this.errEnd;
      if ( ref ) {
         if ( ref instanceof Array )
            this.refs.concat( ref );
         else
            this.refs.push( ref );
         for ( var i in this.refs )
            $( this.refs[i] ).addClass( "ui-state-error" );
      }
      $(this.element).html( this.logStart + this.content + this.logEnd ).show();
   },

   hasError: function()
   {
      if ( this.refs.length )
         return true;
      return false;
   },
});

我可以向其中添加错误消息，以及对将进入错误状态的页面元素的引用.我用它来验证对话框.在addError"方法中，我可以传入一个 id 或一组 id，如下所示:

I can add error messages into it, and references to page elements that is will put into an error state. I use it to validate dialogs. In the "addError" method I can pass in a single id, or an array of ids, like this:

$( "#registerDialogError" ).miniErrorLog(
   'addError',
   "Your passwords don't match.",
   [ "#registerDialogPassword1", "#registerDialogPassword2" ] );

但是当我传入一个 id 数组时，它不起作用.问题在于以下几行(我认为):

But when I pass in an array of id's it doesn't work. The problem is in the following lines (i think):

if ( ref instanceof Array )
   this.refs.concat( ref );
else
   this.refs.push( ref );

为什么那个 concat 不起作用.this.refs 和 ref 都是数组.那么为什么 concat 不起作用?

Why doesn't that concat work. this.refs and ref are both arrays. So why doesn't the concat work?

奖励:我在这个小部件中做了什么愚蠢的事情吗?这是我的第一个.

Bonus: am I doing anything else dumb in this widget? It's my first one.

推荐答案

concat方法不会改变原数组，需要重新赋值.

The concat method doesn't change the original array, you need to reassign it.

if ( ref instanceof Array )
   this.refs = this.refs.concat( ref );
else
   this.refs.push( ref );

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