textbox validation in javascript

[Yell Srik]

I want to do a validation of my checkbox so that the only valid values that are allowed are
a to z, A to Z, aa to zz and AA to ZZ.

i am using the following code to acheive this:

  
function fnCheck (form) {
 TestVar = isNumberString (form.regno.value)
 if (TestVar != 1)
 alert("TestVar is: "+TestVar);
 alert ("Please enter valid values only");
 }
 
 function isNumberString (InString)  {
 if(InString.length==0 || InString.length>2) return (false);
 var RefString="/^[a-z],^[aa-zz],^[AA-ZZ],^[A-Z]";
 alert(RefString);
 for (Count=0; Count < InString.length; Count++)  {
 TempChar= InString.substring (Count, Count+1);
 alert(TempChar);
 if (RefString.indexOf (TempChar, 0)==-1)
 return (false);
 }
 return (true);
 }
 

But it is displaying the alert message even if i enter a valid value like 'aa'?

Can u tell me where i am going wrong?? I want to know if my reference string is given properly?

Thanks in advance.

[Eric Pascarello]

um, why are you checking for 1 when it is returning true/false?

Eric