charAt() comparison

Icemann · Feb 19, 2001

I'm using JavaScript to validate information on a form prior to submission and I've run into a snag. One field on the form is for an order number which must begin with the letter 'n' (either upper or lower case). I'm using the following code to check for the leading 'n' using onSubmit to access the function:
if(document.forms[0].ord_nbr.value.charAt(0) != n) {
alert("......&quot

;
return false;
}
I've tried surrounding the 'n' on the right side of the comparison with single quotes, double quotes, parenthesis and nothing seems to work. I know there must be a simple solution to this.

Using another alert, I can see that the charAt() method is catching the correct value for the first character in the field.

Thanks, JS newbie

AndrewGrabovsky · Feb 19, 2001

Hi Icemann!
You didn't write the rest of your code, maybe the problem is there.
Anyway, here is a code that I checked just now:

<script>
function check() {
if (document.forms[0].ord_nbr.value.charAt(0) != "n&quot

{
alert("error in input!&quot

;
return false;
}
else alert("OK&quot

;
}
</script>
</head>
<body>

<form>
<input type=text name=ord_nbr>
<input type=submit onclick="check()">
</form>

It works. 'N' should be with single or double quotes.

Enjoy!

Andrew | starway@mail.com

Icemann · Feb 20, 2001

Andrew,

You were absolutely right. I had my blinders on trying to figure out why I couldn't compare the strings. I was actually validating for three possibilities in the if statement and I had an || where I needed an &&.

Thanks

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charAt() comparison

Icemann

Programmer

AndrewGrabovsky

Programmer

Icemann

Programmer

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