js 时间校验

<script   language=javascript>   
  String.prototype.isTime   =   function()   
  {   
      var   r   =   this.match(/^(\d{1,4})(-|\/)(\d{1,2})\2(\d{1,2})   (\d{1,2}):(\d{1,2}):(\d{1,2})$/);     
      if(r==null)return   false;   var   d   =   new   Date(r[1],   r[3]-1,r[4],r[5],r[6],r[7]);     
      return   (d.getFullYear()==r[1]&&(d.getMonth()+1)==r[3]&&d.getDate()==r[4]&&d.getHours()==r[5]&&d.getMinutes()==r[6]&&d.getSeconds()==r[7]);   
  }   
  alert("2002-1-31   12:34:56".isTime());   
  alert("2001-2-29   12:54:56".isTime());   
  alert("2002-1-41   12:00:00".isTime());   
  </script>