JS对select控件option选项的增删改查示例代码

//动态创建select
function createSelect()
{
var mySelect = document.createElement("select");
mySelect.id = "mySelect";
document.body.appendChild(mySelect);
}

//添加选项option
function addOption()
{
//根据id查找对象，
var obj=document.getElementById('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
}

//删除所有选项option
function removeAll()
{
var obj=document.getElementById('mySelect');
obj.options.length=0;
}

//删除一个选项option
function removeOne()
{
var obj=document.getElementById('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);
}

//获得选项option的文本
var obj=document.getElementById('mySelect');
var index=obj.selectedIndex; //序号，取当前选中选项的序号
var val = obj.options[index].text;

//修改选项option
var obj=document.getElementById('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");