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");