关于Html中Select的操作

来源：互联网发布：淘宝一元拍卖真的吗编辑：程序博客网时间：2024/05/16 15:51

select的添加元素、读取元素

1、在HTML中增加控件

<div>    <label for="subject">主 题:</label>    <input type="text" id="subject" style="width:40%"><select name="select" id="subjectselect" onchange="getSubSelContent(this.value,this.options[this.selectedIndex].text)"></select><input type="button" value = "增加主题" onclick="AddSubject();"></br></div>

2、JavaScript中增加响应函数

<script>window.onload=function(){        var obj=document.getElementById('subjectselect'); var counts=0;var arr = new Array("选择主题","现状","问题","潜力","特征","规律","措施建议","综合探讨","方案","报告","技术分享");counts=arr.length;var i;for (i=0;i<counts; i++){  obj.options.add(new Option(arr[i],i)); //这个兼容IE与firefox }}function getSubSelContent(value,content){   var obj = document.getElementById('subject');    //alert ("选中的值是"+value+"选中的内容是"+content);   if(value!=0)     obj.value = (content);   }function AddSubject(){  var subVal = document.getElementById('subject').value;    if(subVal=='') {    alert ('主题值为空，请输入主题！')    return;  }     var i=0;  var subValExisted = false;  var OptionsLength = document.getElementById('subjectselect').options.length;  for(i=0;i<OptionsLength;i++)  {      if(document.getElementById('subjectselect').options[i].text == subVal)      {          subValExisted = true;          break;      }  }  if(!subValExisted)    document.getElementById('subjectselect').options.add(new Option(subVal,OptionsLength));  else    alert ('"'+subVal+'"'+'已存在');}</script>

0 0