js下拉框里超过变成省略号_表单特效

<meta http-equiv="Content-Type" content="text/html; charset=utf-8"> <title>脚本之家 www.jb51.net js下拉框省略号</title> <select id="a"> <option slected="slected">下拉框里的字太多了，下拉框会变长，然后把版面挤乱了，多余的如何显示成省略号？</option> <option>或者限制住下拉框的跨度也行？</option> <option>style="width:100px;"</option> <option>这种已经试过了，没用！/option> </option></select> <script type="text/javascript"> function cutOption(selectObj , length) { this.selectObj = selectObj; this.length = length; } cutOption.prototype.init = function() { this.options = this.selectObj.getElementsByTagName('option'); for(i=0 , j=this.options.length ; i<j ; i++ ) { text = this.options[i].firstChild.nodeValue; if(text.length<=this.length) { return; } else { this.options[i].innerHTML = text.substring(0,this.length) + '...'; } } } obj = document.getElementById('a'); //想要几个字就改第二个参数; var optionClass = new cutOption(obj , 2); optionClass.init(); </script>
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