How do I listen for changes to a RadioGroup's selected value using JQuery?
I need to register a handler for a group of radio buttons. I'm using JQuery and hoped that its .change method would accomplish this. However I have not experienced the desired behavoir.
Here is a sample snippet I've written. Sadly, the "radioValueChanged" is only called on the initial load. Selecting either true / false does not trigger the handler.
<html>
<script src="jquery-1.4.2.min.js" type="text/javascript"></script>
<form id="myForm">
<div id="Question1Wrapper">
<div>
<input type="radio" name="controlQuestion" id="valueFalse" value="0" />
<label for="valueFalse">
False</label>
</div>
<div>
<input type="radio" name="controlQuestion" id="valueTrue" value="1" />
<label for="valueTrue">
True</label>
</div>
</div>
<div id="Question2Wrapper">
<div>
<label for="optionalTextBox">
This is only visible when the above is true</label>
<input type="text" name="optionalTextBox" id="optionalTextBox" value="" />
</div>
</div>
<script type="text/javascript">
jQuery(document).ready(function ()
{
$("#controlQuestion").change(radioValueChanged('controlQuestion'));
})
function radioValueChanged(radioName)
{
radioValue = $('input[name=' + radioName + ']:checked', '#myForm').val();
alert(radioValue);
if(radioValue == 'undefined' || radioValue == "0")
{
$('#Question2Wrapper:visible').hide();
}
else
{
$('#Question2Wrapper:visible').show();
}
}
</script>
</form>
Answer
There are a few issues here.
You are immediately running
radioValueChanged('controlQuestion')upon script execution because that is a method call and not a function assignment.The selector
$("#controlQuestion")is wrong, you don't have any elements with id ofcontrolQuestion.The
radioValueChangedmethod is not properly handling values as they would be passed to a jQuery event handler.
You could try something like the following:
jQuery(document).ready(function ()
{
$("input[name='controlQuestion']").change(radioValueChanged);
})
function radioValueChanged()
{
radioValue = $(this).val();
alert(radioValue);
if($(this).is(":checked") && radioValue == "0")
{
$('#Question2Wrapper').hide();
}
else
{
$('#Question2Wrapper').show();
}
}
In all honesty I'm not sure if that is the actual logic you are looking for with the if statement, but hopefully this will provide a basis for you to correct the current code.