Question

I have an aspx page that uses a master page. On this page I have a group of radio buttons. I need to get at the checked property for each of the elements in the radio button group in javascript. Before the page was converted to use a master page, the following javascript code worked just fine:

if((!f.rblRegUseVehicles[0].checked) && (!f.rblRegUseVehicles[1].checked)) {     isValid = 'false'; } 

f is the reference to the form. This worked just fine.

When the page was chanded to use a Master Page, I changed the javascript to the following:

if((!f.<%=rblRegUseVehicles.ClientID%>[0].checked) && (!f.<%=rblRegUseVehicles.ClientID%>[1].checked)) {     isValid = 'false'; } 

Now, the javascript is failing because it can’t find the element. In the ‘View Source’ I have elements with the name:

<input id='ctl00_cphContent_rblRegUseVehicles_0' type='radio' name='ctl00$cphContent$rblRegUseVehicles' value='Yes' />  <input id='ctl00_cphContent_rblRegUseVehicles_1' type='radio' name='ctl00$cphContent$rblRegUseVehicles' value='No' /> 

The only code that works is

document.<%=Form.ClientID%>.<%=rblRegUseVehicles.ClientID%>_0.checked 

I want the javascript to reference the array like before the page was converted to use a Master Page. How can I do that?

Answer 1

If you want to explore the idea of using jQuery rather than straight javascript, this should do the trick for you.

if ( $('input[id*=rblRegUseVehicles]:checked').length < 0 ) isValid = 'false'; 

The selector gets all checked radiobuttons who’s id contains ‘rblRegUseVehicles’.

Edit

If you want to stick with your original script,using UniqueID rather than ClientID may work

if((!f.<%=rblRegUseVehicles.UniqueID%>[0].checked) && (!f.<%=rblRegUseVehicles.UniqueID%>[1].checked)) {     isValid = 'false'; }