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amacfarl
10-03-2003, 07:34 AM
Folks,

I am new to JavaScript, but not new to Java. I have a few questions:

1) How do I validate that a field contains only text or numbers?

2) I have two submit buttons in my form. The form has onSubmit="return check()". In the check() method I validate the form. I also what to find out which submit button was clicked. How do I do this?

To develop Java programs I have several resources which outline what methods and attrbiutes are available. In JavaScript however I dont. In addition, when I make a mistake in Java I get an error message, whilst when I make a mistake in JavaScript, I get nothing, just the code does not run.

Is there any recommendation that you have that will make developing JavaScript easier.

Thanks in advance
Angus
pyro
10-03-2003, 07:47 AM
1) If the if statement evaluates, the form fields contains letters, numbers, and the understrike. Other characters will cause it to break.

if (/^[\w\d]+$/.test(document.formname.fieldname.value)) {

2) You could pass an argument to the function when you call it:

<input type="button" value="Go 1" onclick="someFunction('1');">
<input type="button" value="Go 1" onclick="someFunction('2');">

Now, you can just check if 1 or 2 is set, and you'll know which buttons was clicked.

3) Mozilla and Netscape have a JavaScript debugger called Venkman. Mozilla 1.4 comes with it, but for older versions, you might have to download separatly. Also, in Mozilla/Netscape, you can type javascript# in the addressbar to get errors.
Charles
10-03-2003, 07:53 AM
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
"http://www.w3.org/TR/html4/strict.dtd">
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta name="Content-Script-Type" content="text/javascript">
<title>Example</title>

<style type="text/css">
<!--
label {display:block; margin:1em 0em}
input {display:block}
-->
</style>

<script type="text/javascript">
<!--
function validate (f) {
alert (f.submitButton.name)
return false;
}
// -->
</script>

<form action="" onsubmit="return validate(this)">
<div>
<label>Foo<input type="text" onchange="if (!/^[\d\w]+$/.test(this.value)) {alert('That would not appear to be a valid foo.'); this.value=''; this.focus()}"></label>
<button name="submit1" onclick="this.form.submitButton = this" type="submit">Submit</button>
<button name="submit2" onclick="this.form.submitButton = this" type="submit">Submit</button>
</div>
</form>
amacfarl
10-03-2003, 08:01 AM
Thanks to you both!

I have one followup question...

if (/^[\w\d]+$/.test(document.formname.fieldname.value))

Can you direct me do any further information about the use of /^[\w\d]+$/ syntax. I.e. is it any between the /'s.

Therefore... if I what to exclude £,!&¬ would the syntax be

if (/£,!&¬.text(field))
return false // field contains incorrect values
else
return true

THANKS!
Charles
10-03-2003, 08:14 AM
See http://devedge.netscape.com/library/manuals/2000/javascript/1.3/guide/regexp.html but be careful. A full 13% of users do not use JavaScript. It's important to make sure that your page sitll works for those good people.
pyro
10-03-2003, 08:16 AM
You'd want to add additional chacters between the [ and the ] as that is used to define the character set. Take a look at the link Charles provided for more information.
amacfarl
10-03-2003, 08:34 AM
THANKS!


You both have been a great help