Basic JavaScript Form Validation

[carlg]

I want to validate an HTML form using Javascript.

Here is what I am doing

User clicks submit button for form
Data entered is bad, javascript sends out an alert box to say bad data, but how do I get the form to not get submitted?

I'm using the onClick event for the submit button.

My javascript looks something like this

function verify()
{
if (baddata)
{
alert "bad data"
}}

 

[mbrooks]

Here you go

<script type="text/javascript">
<!--//
function allowSubmit() {

	/* do something here */

	if (bad) {
		d.allow.disabled = true;
	}
}
//-->
</script>

<form onSubmit="allowSubmit()">
	<input type="submit" name="allow" value="Submit">
</form>

M. Brooks

http://mbrooks.info

 

[carlg]

Thank You!!

 

[mbrooks]

The d.allow.disabled should actually be

document.[i]form_name[/i].allow.disabled

M. Brooks

http://mbrooks.info

 

[carlg]

Seems like it still submits my form

Here's the JS


function abc(){
document.empadd.addbutton.disabled=true;
alert ("AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA");
}



Here's the form


<FORM NAME="empadd" METHOD="POST" onSubmit="abc()">
<INPUT NAME="addbutton" TYPE="submit" VALUE="Submit">
</FORM>

 

[carlg]

Got it

Here is what I did


function abc(){
alert ("AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA");
return false;
}



Here's the form


<FORM NAME="empadd" METHOD="POST" onSubmit="return abc()">
<INPUT NAME="addbutton" TYPE="submit" VALUE="Submit">
</FORM>

 

[mbrooks]

<script type="text/javascript">
<!--//
function allowSubmit() {

    /* do something here */

    var d = document.empadd;

    if (good) {
        d.submit();
    }
    else {
        d.addbutton.disabled = true;
    }
}
//-->
</script>

<FORM NAME="empadd" METHOD="POST">
        <INPUT NAME="addbutton" TYPE="button" VALUE="Submit" onClick="allowSubmit()">
</FORM>

M. Brooks

http://mbrooks.info

 

[carlg]

Ah, now i see

Looks like there's 2 different ways.


Thanks for the help!!!

Carl