JS和CSS限制页面显示的字符长度

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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);