jquery中 $.expr使用实例介绍

 
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<script type="text/javascript"> 
$(function() { 
//初始测试数据 
var init=function(){ 
$("#con1").add("#con3").data("key","10001"); 
}; 
init(); 
var select="mytest"; 
var name="key"; 
//定义一个新选择器 
$.expr[ ":" ][ select ] = function( elem ) { 
return !!$.data( elem, name ); 
}; 
//使用 
$("div:mytest").each(function(){ 
alert(this.id);//结果:con1 con3 
}) 
}); 
</script> 
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<body> 
<div id="con1"></div> 
<div id="con2"></div> 
<div id="con3"></div> 
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