Create yourself a library of simple type checks, something like this:
Code:
 
Function IsPunct($sCharacter)
	$IsPunct=InStr("!,.?':;-"+'"',$sCharacter)
	Exit 0
EndFunction
 
Function IsXDigit($sCharacter)
	$IsXDigit=InStr("1234567890ABCDEF",$sCharacter)
	Exit 0
EndFunction
 
Function IsDigit($sCharacter)
	$IsDigit=InStr("1234567890",$sCharacter)
	Exit 0
EndFunction
 
Function IsLower($sCharacter)
	Dim $OldSetting
	$OldSetting=SetOption("CaseSensitivity","ON")
	$IsLower=InStr("abcdefghijklmnopqrstuvwxyz",$sCharacter)
	$OldSetting=SetOption("CaseSensitivity",$OldSetting)
	Exit 0
EndFunction
 
Function IsUpper($sCharacter)
	Dim $OldSetting
	$OldSetting=SetOption("CaseSensitivity","ON")
	$IsUpper=InStr("ABCDEFGHIJKLMNOPQRSTUVWXYZ",$sCharacter)
	$OldSetting=SetOption("CaseSensitivity",$OldSetting)
	Exit 0
EndFunction
 
Function IsAlpha($sCharacter)
	$IsAlpha=IsUpper($sCharacter) | IsLower($sCharacter)
	Exit 0
EndFunction


Now you can check the types simply by saying:
Code:
$c="A"
If IsUpper($c) $c " is upper case" EndIf

$c="8"
If IsDigit($c) or IsDigit($c) $c " is either a letter or a number" EndIf