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I needed to detect a mixed case string in classic ASP. I define a mixed case string as containing both upper and lower case characters, like AuxagGsrLpa. I could not find a free function on the web to make this decision, so I wrote one.

<%
	Function isMixedCase( str )
		'detects mixed case strings using the english alphabet
		'ignores spaces and other non-alphabetic characters
		str = trim( str )
		isMixed = false
		lastCase = ""
		for i=1 to len( str )
			currentChar = mid( str, i, 1 )
			if asc( currentChar ) >= 65 and asc( currentChar ) <= 90 then
				if lastCase <> "" and lastCase <> "upper" then
					isMixed = true
					exit for
				else
					lastCase = "upper"
				end if
			else
				if asc( currentChar ) >= 97 and asc( currentChar ) <= 122 then
					'lower
					if lastCase <> "" and lastCase <> "lower" then
						isMixed = true
						exit for
					else
						lastCase = "lower"
					end if
				else
					lastCase = ""
				end if
			end if
		next
		if isMixed then
			isMixedCase = true
		else
			isMixedCase = false
		end if
	End Function
%>

Here are a few test strings to demonstrate the functionality:


<% response.write "Hello " & isMixedCase( "Hello " ) & " <br>" response.write "hello! " & isMixedCase( "hello!" ) & " <br>" response.write "HELLO " & isMixedCase( "HELLO " ) & " <br>" response.write "hello there " & isMixedCase( "hello there" ) & " <br>" response.write "hellothere " & isMixedCase( "hellothere" ) & " <br>" response.write "hellotherE " & isMixedCase( "hellotherE" ) & " <br>" %>

Here is the resulting HTML output of the tests:

Hello True
hello! False
HELLO False
hello there False
hellothere False
hellotherE True

The goal of this page is to put two MD5 code samples on the same web page, one for ASP classic and one for ASP.NET. String formatting (like ASCII vs UTF-8) can trip up coding these two routines. These two code samples will produce the same MD5 hash output.

Classic ASP/VBScript MD5

The ASP code is simple once you have a copy of md5.asp from http://frez.co.uk. The only file in the ZIP that you need is md5.asp.


<!--#include file="md5.asp"-->
<% response.write md5("[email protected]") %>


ASP.NET MD5

The keys to getting the .net output to match are encoding.ascii and toString("x2").

<%@ Import Namespace="System.Security.Cryptography" %>   
<script language="VB" runat="server">

	Public Sub Page_Load( sender As Object, e As EventArgs )

		Dim strPlainText as String = "[email protected]"
  		
		dim md5Hasher as MD5 = MD5.create( )
		
		dim result as byte( ) = md5Hasher.computeHash( encoding.ascii.getBytes( strPlainText))
		
		for each singleByte as byte in result
			response.write ( singleByte.ToString("x2") )
		next
		
	End Sub

</script>