Javascript Validate Form Fields

**RobB** · Jul 23 '05, 04:48 PM

Re: Javascript Validate Form Fields

Colin Graham wrote:[color=blue]
> Hi there,
>
> Im very new to javascript and this is my first bit of javascript
> coding. I have to write a validation check for two fields that they
> don't contain all the same characters e.g.,
>
> field 1 = 111111 field 2 = 11111111
>
> OR
>
> field 1 = 000000 field 2 = 00000000
>
> my script wants to check to see if this is happening and display an
> error message.
>
> I would also be agreatful if anyone could point me towards any
> javascript code banks on the web as this would help speed up my
> learning.
>
> any help greatly appreciated.
>
> Thanks
>
> Colin[/color]

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"
"http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<title>untitled </title>
<script type="text/javascript">

function checkit(els)
{
//get field
var field = els.something;
//strip whitespace
field.value = field.value.rep lace(/\s/g, '');
//empty?
if (/^$/.test(field.val ue))
{
alert('Please enter something.');
field.focus();
return false;
}
//get first character
var first = field.value.mat ch(/^./);
if (first)
{
//make it a regular expression
var re = new RegExp(first[0], 'g');
//remove all instances of it, test for empty field
if (/^$/.test(field.val ue.replace(re, '')))
{
alert('Entries must not consist of all the same character.');
field.focus();
field.select();
//abort submit
return false;
}
//pro-life
return true;
}
}

</script>
</head>
<body>

<form onsubmit="retur n checkit(this.el ements)">
<input type="text" name="something " value="" />
<input type="submit" />
</form>
</body>
</html>

Studying 'code banks' (imo) will slow down, not speed up your progress.
You'll need to read some good tutorials/textbooks and progress step by
step. Here's a good one:

http://www.amazon.com/gp/reader/0072191279/ref=sib_dp_pt/002-5845044-5143218#reader-link

Regular-Expressions.info - Regex Tutorial, Examples and Reference - Regexp Patterns

http://www.regular-expressions.com/tutorial.html

At Regular-Expressions.info you will find a wide range of in-depth information about a powerful search pattern language called regular expressions.

Javascript Validate Form Fields

Javascript Validate Form Fields

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