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In the following page, with Firefox the remove button submits the form, but the add button doesn't. How do I prevent the remove button from submitting the form?
<html>
<head>
<script type="text/javascript" src="jquery-1.3.2.min.js"></script>
<script type="text/javascript">
function addItem() {
var v = $('form :hidden:last').attr('name');
var n = /(.*)input/.exec(v);
var newPrefix;
if ( n[1].length == 0 ) {
newPrefix = '1';
} else {
newPrefix = parseInt(n[1])+1;
}
var oldElem = $('form tr:last');
var newElem = oldElem.clone(true);
var lastHidden = $('form :hidden:last');
lastHidden.val(newPrefix);
var pat = '=\"'+n[1]+'input';
newElem.html(newElem.html().replace(new RegExp(pat, 'g'), '=\"'+newPrefix+'input'));
newElem.appendTo('table');
$('form :hidden:last').val('');
}
function removeItem() {
var rows = $('form tr');
if ( rows.length > 2 ) {
rows[rows.length-1].html('');
$('form :hidden:last').val('');
} else {
alert('Cannot remove any more rows');
}
}
</script>
</head>
<body>
<form autocomplete="off" method="post" action="">
<p>Title:<input type="text" /></p>
<button onclick="addItem(); return false;">Add Item</button>
<button onclick="removeItem(); return false;">Remove Last Item</button>
<table>
<th>Name</th>
<tr>
<td><input type="text" id="input1" name="input1" /></td>
<td><input type="hidden" id="input2" name="input2" /></td>
</tr>
</table>
<input id="submit" type="submit" name="submit" value="Submit">
</form>
</body>
</html>
Here's a simple approach:
You're using an HTML5 button element. Remember the reason is this button has a default behavior of submit, as stated in the W3 specification as seen here: W3C HTML5 Button
So you need to specify its type explicitly:
in order to override the default submit type. I just want to point out the reason why this happens =)
=)
I'm not able to test this right now, but I would think you could use jQuery's preventDefault method.
The function removeItem actually contains an error, which makes the form button do it's default behaviour (submitting the form). The javascript error console will usually give a pointer in this case.
Check out the function removeItem in the javascript part:
The line:
doesn't work. Try this instead: