js 操作select和option常用代码整理

<select id="mySelect"> 
　　<option value="1">one</option> 
　　<option value="2">two</option> 
　　<option value="3">three</option> 
</select> 

$("#mySelect").val(); //获取选中记录的value值 
$("#mySelect option:selected").text(); //获取选中记录的text值 

var obj = document.getElementById("mySelect");
obj.add(new Option("4","4")); 

var obj = document.getElementById("mySelect");
obj.options.length = 0; 

var obj = document.getElementById("mySelect");
var index = obj.selectedIndex;
obj.options.remove(index); 

var obj = document.getElementById("mySelect"); 
var index = obj.selectedIndex; 
obj.options[index] = new Option("three",3); //更改对应的值 
obj.options[index].selected = true; //保持选中状态 

var obj = document.getElementById("mySelect"); 
obj.parentNode.removeChild(obj); //移除当前对象 

$("#mySelect").change(function(){ 
　　//添加所需要执行的操作代码
}) 

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

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 
} 

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

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); 
} 

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; 

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; 

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"); 

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