JavaScript 实现 Iterator 迭代器模式实例

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<title>无标题 1</title>
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<script type="text/javascript" language="javascript">
 ///@定义一个迭代器对象
 function Iterator(arr)
 {
  this.obj=arr;
  this.length=this.obj.length;
  this.index=0; //从前往后
 }
 Iterator.prototype=
 {
  current:function()
  {
   return this.obj[this.index-1];
  },
  first:function()
  {
   return this.obj[0];
  },
  last:function()
  {
   return this.obj[this.length-1];
  },
  hasNext:function()
  {
   this.index=this.index+1;
   if(this.index>this.length || null==this.obj[this.index-1])
    return false;
   return true;
  }
 }
 Array.prototype.createIterator=function()
 {
  return new Iterator(this);
 }
 var test=['abc1','abc2','abc3'];
 var iter=test.createIterator();
 while(iter.hasNext())
 {
  var tempArr=iter.current();
  alert(tempArr);
 }
</script>
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