How to populate dependant <html:select>

[Sameer Sb]

Hi ,
I have two drop down boxes; one contains "State" and other contains "City".
I wish to populate Cities according to the value selected in State Drop down.
For this I would like to use Ajax to avoid page refresh. And for fetching values in City I am using Struts Action class to give call to server side code.
Does anyone know; How to do this?

Thanks in advance.

[Sagar Rohankar]

Sameer Sb wrote:Does anyone know; How to do this?[/size]

Do you have any knowledge of AJAX, if no, this link will give you start.

[Sameer Sb]

Hi Sagar,

Thanks for reply.
I know ajax a little bit and know how to build URL and call struts action from a javascript.
I am getting data from my DAO classes format those in Struts Action class in format id,value;id,value;id,value.
Could also separate this in further step by using split and could get id and value in a for loop.
my question is then how to update the dependant <html:select> on the jsp?

[Sagar Rohankar]

First thing first, this is not the question for Struts section. Ask AJAX question in HTML-Jsvascript section.

Sameer Sb wrote:
I am getting data from my DAO classes format those in Struts Action class in format id,value;id,value;id,value.

Called JSON

Sameer Sb wrote:my question is then how to update the dependant <html:select> on the jsp?

Once you get that JSON string on client side, evalualte/parse it using function eval() and "write" the HTML or TEXT to select element, something like this

var data = eval("(" + request.responseText + ")");
if(data)
{ 
       var select = document.form.select; 
       select.options.length = 0; 
       select.options[0] = new Option(data.key1);        
} 

(please look for the correct syntax)