Disable form submit with illegal words

**acoder** · Aug 11 '08, 07:13 PM

It won't prevent spam bots. Someone could just disable JavaScript.

Anyhow, the way to do this is in the normal validation way:
[code=html]<form ... onsubmit="retur n validate()">[/code]then validate() would return false if there are illegal words (and thereby prevent submission) and true otherwise.

**RamananKalirajan** · Aug 12 '08, 05:57 AM

Hi, what did you mean by Illegal words, You can validate the form as Mr. Coder suggested or if you want to be more specific. onKeyPress event for TextArea write your own logic, so that the user can only enter character without special symbol and numbers. This alone can be done u can't check what he entered is meaningful or not while the user enters the text over there. If any doubts post it back I will try to help you out

Regards
Ramanan Kalirajan

**Jacotheron** · Aug 15 '08, 02:32 PM

Originally posted by RamananKaliraja n

Hi, what did you mean by Illegal words, You can validate the form as Mr. Coder suggested or if you want to be more specific. onKeyPress event for TextArea write your own logic, so that the user can only enter character without special symbol and numbers. This alone can be done u can't check what he entered is meaningful or not while the user enters the text over there. If any doubts post it back I will try to help you out

Regards
Ramanan Kalirajan

The illegal words/characters are to be specified in JS and be validated prior to form submit. How do I tell JS to check for it in the text area? That is where my problem is. The characters are: "<>?[]" The idea is to prevent them from sending me links to other sites i don't have time to visit. (these messages are about 120 k each to download and every day there are a lot of them)

Thank you for the help

**acoder** · Aug 16 '08, 12:12 PM

Use a regular expression, e.g. [<>\?\[\]], to test the input from the text area using the match() method.

**RamananKalirajan** · Aug 18 '08, 05:13 AM

Originally posted by Jacotheron

The illegal words/characters are to be specified in JS and be validated prior to form submit. How do I tell JS to check for it in the text area? That is where my problem is. The characters are: "<>?[]" The idea is to prevent them from sending me links to other sites i don't have time to visit. (these messages are about 120 k each to download and every day there are a lot of them)

Thank you for the help

Just check this one. This may the thing what u are looking for

[HTML]<html>
<textarea onkeypress="ret urn checkThis(event )">
</textarea>
</html>
<script type="text/javascript">
function checkThis(e)
{
var ch = e.keyCode;
if(ch!=60&&ch!= 62&&ch!=63&&ch! =91&&ch!=93)
return true;
return false;
}
</script>[/HTML]

Regards
Ramanan Kalirajan

**Jacotheron** · Aug 21 '08, 06:24 PM

Originally posted by RamananKaliraja n

Just check this one. This may the thing what u are looking for

[HTML]<html>
<textarea onkeypress="ret urn checkThis(event )">
</textarea>
</html>
<script type="text/javascript">
function checkThis(e)
{
var ch = e.keyCode;
if(ch!=60&&ch!= 62&&ch!=63&&ch! =91&&ch!=93)
return true;
return false;
}
</script>[/HTML]

I tried this script, but for some reason it does not prevent the use of illegal characters and it still gets through.

Thank you for the help

**RamananKalirajan** · Aug 22 '08, 04:08 AM

Originally posted by Jacotheron

I tried this script, but for some reason it does not prevent the use of illegal characters and it still gets through.

Thank you for the help

Hello wether the code is showing any error. Or it doesn't restrict the illegal characters. The code was working fine for me. Please tell the problem u faced

Regards
Ramanan Kalirajan

**Jacotheron** · Aug 26 '08, 04:16 PM

Originally posted by RamananKaliraja n

Hello wether the code is showing any error. Or it doesn't restrict the illegal characters. The code was working fine for me. Please tell the problem u faced

No code error is displayed and the submission is not prevented when entering the illegal characters.

Thank You for the help

**RamananKalirajan** · Aug 27 '08, 04:35 AM

Originally posted by Jacotheron

No code error is displayed and the submission is not prevented when entering the illegal characters.

Thank You for the help

I dont know why that code was not working for you. But any how try this one. This amy surely help u out.

[HTML]<html>
<head>
<script type="text/javascript">
var flag=0;
function check(ths)
{
var x = new Array("<",">"," ?","[","]");
var data = ths.value;
for(var i=0;i<x.length; i++)
{
if(data.indexOf (x[i])>0)
{
alert("coming") ;
flag=1;
break;
}
flag=0;
}
if(flag==1)
document.getEle mentById('mysub mit').disabled= true;
else
document.getEle mentById('mysub mit').disabled= false;
}
</script>
</head>
<form action="demo.ht ml">
<textarea onkeyup="check( this)">
</textarea>
<br/>
<input type="submit" value="submit" id="mySubmit">
</form>
</html>[/HTML]

Regards
Ramanan Kalirajan

**gits** · Aug 27 '08, 10:17 AM

with the suggested regExp by acoder you could cut down the entire thing to the following simple function:

[HTML]<html>
<head>
<script type="text/javascript">
function check(node) {
var re = new RegExp('[<>\?\\[\\]]', 'g');
document.getEle mentById('mySub mit').disabled = re.test(node.va lue);
}
</script>
</head>
<form action="demo.ht ml">
<textarea onkeyup="check( this)">
</textarea>
<br/>
<input type="submit" value="submit" id="mySubmit"/>
</form>
</html>[/HTML]
kind regards

**Jacotheron** · Aug 28 '08, 03:43 PM

Originally posted by gits

with the suggested regExp by acoder you could cut down the entire thing to the following simple function:

[HTML]<html>
<head>
<script type="text/javascript">
function check(node) {
var re = new RegExp('[<>\?\\[\\]]', 'g');
document.getEle mentById('mySub mit').disabled = re.test(node.va lue);
}
</script>
</head>
<form action="demo.ht ml">
<textarea onkeyup="check( this)">
</textarea>
<br/>
<input type="submit" value="submit" id="mySubmit"/>
</form>
</html>[/HTML]

This form works now!

Thank You all for helping e solve this problem

Kind regards
Jacotheron

Disable form submit with illegal words

Disable form submit with illegal words

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