实用的placeholder插件，兼容IE下的placeholder，jquery插件

placeholder在IE下无法兼容 ，下面的插件很好的处理了这个问题，拿去不谢

 /*
  * jQuery placeholder, fix for IE6,7,8,9
  * @website itmyhome.com
  */
 var JPlaceHolder = {
     //检测
     _check : function(){
         return 'placeholder' in document.createElement('input');
     },
     //初始化
     init : function(){
         if(!this._check()){
             this.fix();
         }
     },
     //修复
     fix : function(){
         jQuery(':input[placeholder]').each(function(index, element) {

             var self = $(this), txt = self.attr('placeholder');
             self.wrap($('<div></div>').css({position:'relative', zoom:'1', border:'none', background:'none', padding:'none', margin:'none'}));
             var pos = self.position(), h = self.outerHeight(true), paddingleft = self.css('padding-left');

             var holder = $('<span></span>').text(txt).css({position:'absolute', left:pos.left, top:pos.top, height:h, lienHeight:h, paddingLeft:paddingleft, color:'#aaa'}).appendTo(self.parent());
             self.focusin(function(e) {
                 holder.hide();
             }).focusout(function(e) {
                 if(!self.val()){
                     holder.show();
                 }
             });
             holder.click(function(e) {
                 holder.hide();
                 self.focus();
             });
         });
     }
 };

 //执行
 jQuery(function(){
     JPlaceHolder.init();
 });