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CheckBox - onchange event?

Hi all!

I have a HUGE form (over 250 fields) which contains just about every type of input your could imagine.

The customer would now like to have two of the checkboxes on the form be relative to each other...they'd be performing more like radio buttons, in that if one is checked, the other will uncheck.

I don't think I can do an autopostback, because I don't want the form submitted until all the values are completed and these checkboxes are in the middle of the page.

Can anyone show me a function that I can apply to an onchange event that will check to make sure that if Checkbox1 is selected then Checkbox2 isn't and vice-versa?

1 Solution
add this script to your html head

<script type="text/javascript">
function ReverseCheckBox(sender, linkedControl) {
if (document.getElementById(sender).checked==true) {
document.getElementById(linkedControl).checked = ! document.getElementById(sender).checked;

You must add in code behind the attribute:
onclick="ReverseCheckBox('THE ID OF THE CHECKBOX', 'THE ID OF THE LINKED CHECKBOX');" to every checkbox

your output must become something like:
 <asp:CheckBox ID="CheckBox1" runat="server" onclick="ReverseCheckBox('CheckBox1', 'CheckBox2');"/>
 <asp:CheckBox ID="CheckBox2" runat="server"  onclick="ReverseCheckBox('CheckBox2', 'CheckBox1');"/>

ClassyLinksAuthor Commented:

Thank you!
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