CSS(js)限制页面显示的文本字符长度

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// copyright c by zhangxinxu v1.0 2009-09-05
// http://www.zhangxinxu.com
/* $(".test1").wordLimit(); 自动获取css宽度进行处理，如果css中未对.test1给定宽度，则不起作用
$(".test2").wordLimit(24); 截取字符数，值为大于0的整数，这里表示class为test2的标签内字符数最多24个
*/
(function($){
$.fn.wordLimit = function(num){
this.each(function(){
if(!num){
var copyThis = $(this.cloneNode(true)).hide().css({
'position': 'absolute',
'width': 'auto',
'overflow': 'visible'
});
$(this).after(copyThis);
if(copyThis.width()>$(this).width()){
$(this).text($(this).text().substring(0,$(this).text().length-4));
$(this).html($(this).html()+'...');
copyThis.remove();
$(this).wordLimit();
}else{
copyThis.remove(); //清除复制
return;
}
}else{
var maxwidth=num;
if($(this).text().length>maxwidth){
$(this).text($(this).text().substring(0,maxwidth));
$(this).html($(this).html()+'...');
}
}
});
}
})(jQuery);