Form validation doesn't work in FF [Archive]

whatg

11-11-2010, 10:59 AM

Hi, doing form validation at college just now. The lecturer gave all of us this following example. But it doesn't seem to work in firefox. I have tried my own scripts and they seem to work so have no idea whats happening!

<html>
<head>
<title>Javascript validation program - limits field length and content</title>
<script type="text/javascript">

function ValidateForm()
{
var msg='';
if(document.getElementById('CC').value=='')
{
msg+='- Please enter CC\n\n';
}
else
// Now test if CC is purely 2 capital letters...

{
var CC=RTrim(document.getElementById('CC').value);
// alert(CC);
if (CC.length==2)
{
if (isCHAR(CC)==false)
{
msg+=' - CC not solely 2 capital letters \n\n';
}
}
else
msg+=' - CC not 2 letters in length \n\n';
}

if(document.getElementById('NNNNNN').value=='')
{
msg+='- Please enter NNNNNN \n\n';
}
else
{
// Now test if NNNNNN is purely 6 digits...

var NIdigits=RTrim(document.getElementById('NNNNNN').value);
if (NIdigits.length==6)
{
if (isInteger(NIdigits)==false)
{
msg+=' - NNNNNN not solely digits \n\n';
}
}
else
msg+=' - NNNNNN not 6 digits in length\n\n';
}

// Lastly check if the last field contains only 1 char

if(document.getElementById('C').value=='')
{
msg+='- Please enter C \n\n';

}
else
// Now test if C is a single letter...

{
var C=RTrim(document.getElementById('C').value);

if (C.length==1)
{
if (isCHAR(C)==false)
{
msg+=' - C not a capital letter \n\n';
}
}
else
msg+=' C not 1 character in length';
}
// alert(msg);
if(msg!='')
{
//alert('Here...');
alert('The following fields are empty and/or invalid:\n\n'+msg);
return false
}
else
{
return true
}
}

function RTrim(str){
if (str==null){return null;}
for(var i=str.length-1;str.charAt(i)==" ";i--);
return str.substring(0,i+1);
}

//-------------------------------------------------------------------
// isBlank(value)
// Returns true if value only contains spaces
//-------------------------------------------------------------------
function isBlank(val){
if(val==null){return true;}
for(var i=0;i<val.length;i++) {
if ((val.charAt(i)!=' ')&&(val.charAt(i)!="\t")&&(val.charAt(i)!="\n")&&(val.charAt(i)!="\r")){return false;}
}
return true;
}

//-------------------------------------------------------------------
// isInteger(value)
// Returns true if value contains all digits
//-------------------------------------------------------------------
function isInteger(val){
if (isBlank(val)){return false;}
for(var i=0;i<val.length;i++){
if(!isDigit(val.charAt(i))){return false;}
}
return true;
}
//-------------------------------------------------------------------
// isCHAR(value)
// Returns true if value contains all CHARS
//-------------------------------------------------------------------
function isCHAR(val){
if (isBlank(val)){return false;}
for(var i=0;i<val.length;i++){
if(!isCAPlet(val.charAt(i))){return false;}
}
return true;
}
//-------------------------------------------------------------------
// isDigit(value)
// Returns true if value is a 1-character digit
//-------------------------------------------------------------------
function isDigit(num) {
if (num.length>1){return false;}
var string="1234567890";
if (string.indexOf(num)!=-1){return true;}
return false;
}

//-------------------------------------------------------------------
// isCAPlet(value)
// Returns true if value is a 1-character letter
//-------------------------------------------------------------------
function isCAPlet(num) {
if (num.length>1){return false;}
var string="ABCDEFGHIJKLMNOPQRSTUVWXYZ";
if (string.indexOf(num)!=-1){return true;}
return false;
}
</script>

</head>

<body bgcolor="#FFFFFF">

<form action='http://10.205.3.202/Valid.php' method='POST' onsubmit='return ValidateForm();'>

<H1>Validate NI No</H1>

<p>

NI-No :

<INPUT TYPE="text" id='CC' NAME="CC" SIZE='2' maxlength='2' >
-

<INPUT TYPE="text" id='"NNNNNN"' NAME="NNNNNN" SIZE='6' maxlength='6' >

<INPUT TYPE="text" id='C' NAME="C" SIZE='1' maxlength='1'>

<p>

<INPUT TYPE="submit" id='Process' value="Process" name="submit">

</form>

</body>
</html>

Any help would be great. :thumbsup:

Philip M

11-11-2010, 05:43 PM

You (or your teachers) seem to be using double and single quotes (and capitals and lower-case) randomly. E.g.
<INPUT TYPE="text" id='NNNNNN' NAME="NNNNNN" SIZE='6' maxlength='6' >
That is likely to give rise to problems. Define a consistent policy and stick to it. var x = "" (two double quotes) is to be preferred to var x = '' (two single quotes), as '' can be mistaken for "

You could greatly simplify your code by using regular expressions in place of the long-winded and long-obsolete functions isBlank(), isChar(), isDigit() etc. What a pity that teachers are still serving up this old stuff. :( Is there any other faculty in your college where the syllabus taught is 10 years out of date? :eek:

"Debugging is twice as hard as writing the code in the first place. Therefore, if you write the code as cleverly as possible, you are, by definition, not smart enough to debug it." Brian W. Kernighan