checkbox - PHPBuilder Forums

checkbox

jacob_kochi

My code

for($i=0;$i<10;$i++)
{
print "<input type='checkbox' name='check[]'>";
}

Can any one help me to create a javascript function to check atleast one of the checkbox is checked.

baronmask

Dear jacob_kochi,
actually this is a php forum, hard to ask for javascript help. You'd better to ask in the approriate javascript forum. But maybe this script will help you a little.

The script will do check to all form elements (validate form) and at least one of the checkbox in the form elements should be checked. Please extract the function for suit your need.

<script language="JavaScript">
<!--
function validateForm (form) {
for (var e = 0; e < form.elements.length; e++) {
var el = form.elements[e];
if (el.type == 'text' || el.type == 'textarea' ||
el.type == 'password' || el.type == 'file' ) {
if (el.value == '') {
alert('Please fill out the text field ' + el.name);
el.focus();
return false;
}
}
else if (el.type.indexOf('select') != -1) {
if (el.selectedIndex == -1) {
alert('Please select a value of the select field ' + el.name);
el.focus();
return false;
}
}
else if (el.type == 'radio') {
var group = form[el.name];
var checked = false;
if (!group.length)
checked = el.checked;
else
for (var r = 0; r < group.length; r++)
if ((checked = group[r].checked))
break;
if (!checked) {
alert('Please check one of the radio buttons ' + el.name);
el.focus();
return false;
}
}
else if (el.type == 'checkbox') {
var group = form[el.name];
if (group.length) {
var checked = false;
for (var r = 0; r < group.length; r++)
if ((checked = group[r].checked))
break;
if (!checked) {
alert('Please check one of the checkboxes ' + el.name);
el.focus();
return false;
}
}
}
}
return true;
}

// -->
</script>

.:: Baronmask ::.

lnfreish

I use it like this:

<html>
<head>
<script language="javascript">
var j = 0;

function checkit() {
for (i=0;i<myfrm.check.length;i++) {
if (myfrm.check.checked == true) {
j++;
}
}
window.alert("you have checked " + j + " fields!");
}
</script>
</head>

<body>
<form name="myfrm">
<script language="javascript">
for (i=0;i<10;i++) {
document.write("<input type=checkbox name=check>");
}
</script>
<input type=submit name=submit value=submit onclick=javascript:checkit();>
</form>
</body>

</html>

Weedpacket

Basically - since the problem[*] is the [] in the checkbox's name - you'll want to be looking through a particular property of the form - it's an array containing all the elements, indexed by both name and number. I don't recall what the property is called or how multiple checkboxes will be represented in this form element - I'd be on much more familiar territory if this were a PHP problem. I do seem to recall something on exactly this subject in the user notes of the section on form handling in the PHP manual.

*I guess; no specific problem was actually described.

jacob_kochi

Not working if i put

<input type=checkbox name=check[]>