Signing a string

Hi
Can anyone please show me an example how to sign a string?
I need to Calculate an RFC 2104-compliant HMAC from a string with a private key using  the HmacSHA256  as the hash algorithm and then Convert the resulting value to base64.
i mannaged to create an object  or two but i don't knew how to take from there on.
here is an example of the object i created:
 
'dim myhash as new System.Security.Cryptography.HMACSHA256set
myhash = createobject("System.Security.Cryptography.HMACSHA256")WScript.echo myhash.Hashsize()WScript.echo myhash.key()
and here is another object i created:
set pkey = CreateObject("Chilkat.PrivateKey")
 
but as told before i need help to take it from here on
 

Thanks in advance.

The hash function expects both key and data as byte arrays, so you need to convert your data from String to Byte() first. Try this:

key = "..."
str = "..."

Set text = CreateObject("System.Text.UTF8Encoding")
Set sha256 = CreateObject("System.Security.Cryptography.HMACSHA256")

sha256.Key = text.GetBytes_4(key)
hmac = sha256.ComputeHash_2(text.GetBytes_4(str))

For the base64 encoding I'd suggest to modify Antonin Foller's Base64Encode() function, so that it will work with binary strings instead of normal strings (by replacing the string functions that operate on inData with their binary equivalents, i.e. Asc -> AscB, Mid -> MidB, ...).

Thank you 59cobalt for your help
i'll let you knew after i'll tryit