javascript 对 dropdownlist 的操作

Adding items in drop down list or list box using javascript

 

I have seen lots of questions in diffrent forums for adding items in drop down list or list box using javascript. Below is the script for the same.

 

<script type="text/javascript">

function AddItem(Text,Value)

 {

        // Create an Option object               

var opt = document.createElement("option");

        // Add an Option object to Drop Down/List Box

        document.getElementById("DropDownList").options.add(opt);      

 // Assign text and value to Option object

        opt.text = Text;

        opt.value = Value;

 }

<script /> 

You can use this function in for loop to add more than one item.

 

 

Getting the selected Value of dropdownlist using javascript

 

var roles = document.getElementById("DropDownList ");

     if(roles!=null&& roles.selectedIndex!=-1){

       //Getting value

       rolesVal=roles.options[roles.selectedIndex].value;   

       //Getting text

       rolesVal=roles.options[roles.selectedIndex].text;    

     }

 

 

Removing all the items of dropdownlist using javascript

 

var regions = document.getElementById("DropDownList ");

var len = regions.options.length;

for(i=len-1;i>=0;i--){

         regions.options.remove(i);

     }