js 操作select和option

1.动态创建select

function createSelect(){

var mySelect = document.createElement_x("select");
          mySelect.id = "mySelect";
          document.body.appendChild(mySelect);
      }

2.添加选项option

function addOption(){

//根据id查找对象，
var obj=document.getElementByIdx_x('mySelect');

           //添加一个选项
obj.add(new Option("文本","值"));    //这个只能在IE中有效
         obj.options.add(new Option("text","value")); //这个兼容IE与firefox
     }

3.删除所有选项option

function removeAll(){
var obj=document.getElementByIdx_x('mySelect');
obj.options.length=0;

}

4.删除一个选项option

function removeOne(){
var obj=document.getElementByIdx_x('mySelect');

//index,要删除选项的序号，这里取当前选中选项的序号

var index=obj.selectedIndex;
obj.options.remove(index);
}

5.获得选项option的值

var obj=document.getElementByIdx_x('mySelect');

var index=obj.selectedIndex; //序号，取当前选中选项的序号

var val = obj.options[index].value;

6.获得选项option的文本

var obj=document.getElementByIdx_x('mySelect');

var index=obj.selectedIndex; //序号，取当前选中选项的序号

var val = obj.options[index].text;

7.修改选项option

var obj=document.getElementByIdx_x('mySelect');

var index=obj.selectedIndex; //序号，取当前选中选项的序号

var val = obj.options[index]=new Option("新文本","新值");

8.删除select

      function removeSelect(){
            var mySelect = document.getElementByIdx_x("mySelect");
mySelect.parentNode.removeChild(mySelect);
     }

整个实例的完整代码如下：

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//ZH-CN" "http://www.w3.org/TR/html4/strict.dtd">
<html>
<head>
   <meta http-equiv="Content-Type" content="text/html">
<head>
   <script language=JavaScript>
    function $(id)
    {
     return document.getElementByIdx_x(id)
    }
    function show()
    {
     var selectObj=$("area")
     var myOption=document.createElement_x("option")
     myOption.setAttribute("value","10")
     myOption.appendChild(document.createTextNode("上海"))
     var myOption1=document.createElement_x("option")
     myOption1.setAttribute("value","100")
     myOption1.appendChild(document.createTextNode("南京"))
     selectObj.appendChild(myOption)
     selectObj.appendChild(myOption1)
    }
    function choice()
    {
     var index=$("area").selectedIndex;
     var val=$("area").options[index].getAttribute("value")
     if(val==10)
     {
      var i=$("context").childNodes.length-1;
     var remobj=$("context").childNodes[i];
     remobj.removeNode(true)
      var sh=document.createElement_x("select")
      sh.add(new Option("浦东新区","101"))
      sh.add(new Option("黄浦区","102"))
      sh.add(new Option("徐汇区","103"))
      sh.add(new Option("普陀区","104"))
      $("context").appendChild(sh)
     }
     if(val==100)
     {
      var i=$("context").childNodes.length-1;
     var remobj=$("context").childNodes[i];
     remobj.removeNode(true)
      var nj=document.createElement_x("select")
      nj.add(new Option("玄武区","201"))
      nj.add(new Option("白下区","202"))
      nj.add(new Option("下关区","203"))
      nj.add(new Option("栖霞区","204"))
      $("context").appendChild(nj)
     }
    }
    function calc()
    {
     var x=$("context").childNodes.length-1;
     alert(x)
    }
    function remove()
    {
     var i=$("context").childNodes.length-1;
     var remobj=$("context").childNodes[i];
     remobj.removeNode(true)
    }
   </script>
<body>
<div id="context">
   <select id="area" onchange="choice()">
   </select>
</div>
<input type=button value="显示" onclick="show()">
<input type=button value="计算结点" onclick="calc()">
<input type=button value="删除" onclick="remove()">
</body>
</html>

改进版：在select中添加、修改、删除option元素

整个实例的完整代码如下：

<!doctype html public "-//w3c//dtd html 4.0 transitional//en">
<html>
<head>
<title>javascript select options text value</title>
<meta name="keywords" content="javascript select options text value add modify delete set">
<meta name="description" content="javascript select options text value add modify delete set">
<script language="javascript">

</script>
</head>
<body>
<form name="watch" method="post" action="">
<select id="MySelect" name="keywords" size="10" onchange="watch_sel(this.form)"></select><br>
<script language="javascript">

</script>
<input type="text" name="word" /><br />
<input type="button" value="增加" onclick="watch_add(this.form);" />
<input type="button" value="修改" onclick="watch_mod(this.form);" />
<input type="button" value="删除" onclick="watch_del(this.form);" />
<input type="button" value="保存" onclick="watch_set(this.form);" />
</form>

用一个字符串创建一个数组方法:

</body>
</html>
<script>
function spli(){
datastr="2,2,3,5,6,6";
var str= new Array();
str=datastr.split(",");
for (i=0;i<str.length ;i++ )
{ document.write(str[i]+"<br/>"); }
}
spli();
</script
今天调试了一段js，在ie上运行良好，在火狐上调试出现错误，查资料发现

obj.add(new Option("文本","值")); //这个只能在IE中有效
obj.options.add(new Option("text","value")); //这个兼容IE与firefox

因为这段代码，在网上查资料收藏了这篇文章，实时的温故js

共勉！！

posted on 2012-11-07 17:52 逐梦lj 阅读(22823) 评论(1) 编辑收藏举报