Assuming it is an html form, and that your checkboxes
do have different names, try using "onValidate". It calls a javascript function (that you code yourself) when the form is submitted. The function should return true or false. ie true if at least one box was checked, otherwise false. If it returns false, an error message is displayed and the form will not be submitted.
Here is the basic structure.
CODE
<script type="text/javascript">
// the function must accept these parameters or it will not work
function verifyCheckedBoxes(objForm, objField, fieldValue) {
// your javascript code that counts the total
// number of checked boxes here
// if at least one box was checked, return true. Otherwise, return false here
return true or false here;
}
</script>
<cfform action="theActionPage.cfm" method="post">
Option A <cfinput type="checkbox" name="option_A" value="A" onValidate="verifyCheckedBoxes" message="Check at least one box"><br>
Option B <cfinput type="checkbox" name="option_B" value="B"><br>
Option C <cfinput type="checkbox" name="option_C" value="C"><br>
<cfinput type="submit" name="submitThis">
</cfform>
10 May, 2008 - 10:09 PM
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