Ralph Freshour wrote on 14 Dec 2003 at Sun, 14 Dec 2003 16:00:11
GMT:
I have multiple checkbox's created with an array name because I
have many on the same web page - their names are like:
frm_chk_delete[0]
frm_chk_delete[1]
frm_chk_delete[2]
frm_chk_delete[3]
etc.
Here is my code line that creates each checkbox (the php
variable get incremented of course):
<INPUT TYPE="checkbox" NAME="frm_chk_delete[<?php echo
$php_delete_counter;?>]">Delete
When I click on the Delete button I want to call a JS routine to
check that at least one checknbox has been checked and marked
for deletion when the form submit is called my php file will
detect and delete the checkboxes accordingly.
I'd like to use JS before the submit and make sure at least one
of the checkboxes is checked - how do I loop through these array
name checkboxes in javascript to check their states before
submitting?
It would be easier if they all had the same name, but it can be done
as it is.
<FORM ... onsubmit="return checkBoxes(this)">
function checkBoxes(form) {
var numControls = form.elements.length;
var checks = 0;
// Check every control in the form
for (var i = 0; i < numControls; ++i) {
var element = form.elements[i];
// If the name begins, frm_chk_delete[ ...
if ('frm_chk_delete[' == element.name.substr(0, 15)) {
// ...see if it's checked, and increment counter if it is
if (element.checked) checks++;
}
}
// If none of boxes have been checked, alert the user and cancel
// the submission
if (!checks) {
window.alert('Please check at least one box before submitting');
return false;
}
// If code reaches here, at least one box was checked, so allow
// the form to submit
return true;
}
If it's not guaranteed that only checkboxes will have names that
start with 'frm_chk_delete[', you should also check to make sure that
the element being inspected is a checkbox (use element.type ==
'checkbox').
Hope that helps,
Mike
--
Michael Winter
M.******@blueyonder.co.invalid (replace ".invalid" with ".uk")
