jQuery继承extend用法详解

/直接基于jQuery的扩展,判断是否为空

$.isBlank =function(obj){

return(typeof(obj)=='undefined'||obj==''||obj==null);

}

//直接基于jQuery的扩展,去除html标签,保留内容

$.htmlContent =function(tag){

varreTag = /<(?:.|\s)*?>/g;

returntag.replace(reTag,"");

}

//直接基于jQuery的扩展(方式二)

$.xy = {

sayhello:function(){return"hello";},

saybaybay:function(){return"baybay";}

};

//jQuery类级别的扩展

$.extend({

add:function(a,b){returna+b;},

diff:function(a,b){returna-b}

});

//jQuery对象级别的扩展

$.fn.extend({

getvalue:function(){

returnthis.val();

}

});

html代码

<body>

<scripttype="text/javascript">

document.write("判断是否为空:"+$.isBlank(null));

</script>

<spanclass="myspan"></span>

<scripttype="text/javascript">

document.write("过滤html标签:"+$.htmlContent("<html><body><aid='a1'>a标签</a><divstyle='width:100%'>div标签</div>内容</body></html>")+"<br/>");

document.write("扩展自jQuery类的xy的sayhello方法:"+ $.xy.sayhello()+"</br>");

document.write("扩展自jQuery类的xy的sayhello方法:"+ $.xy.saybaybay()+"</br>");

document.write("基于jQuery类的add法:"+ $.add(3,5)+"</br>");

document.write("基于jQuery类的diff法:"+ $.diff(5,3)+"</br>");

document.write("基于自jQuery类对象的扩展getvalue():"+$("<inputtype='text'value='str'/>").getvalue()+"<br/>");

</script>

</body>