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);