So we are in the process of converting our 19.1 application to 23.0 and I've hit a problem while converting a call to CryptStringToBinaryA.

It's clear to use WStrings etc but CryptStringToBinaryW expects a pointer to the data AND the size of the data. In the ANSI version it was just the Length() but what to pass for the wide version?
We have SizeOfString() that returns the amount of UTF8 bytes but is there such a thing for WString?

External_Function CryptStringToBinary "CryptStringToBinaryW" Crypt32.dll Pointer pszString DWord cchString ;
        DWord dwFlags Pointer pbBinary Pointer pcbBinary Pointer pdwSkip Pointer pdwFlags Returns Boolean
This is what I have currently but have not tested it as I doubt SizeOfString() is correct
Move (CryptStringToBinary(AddressOf(wsBase64),SizeOfString(wsBase64),dwFlags,AddressOf(wsData),AddressOf(dwSize),AddressOf(dwSkip),AddressOf(dwFlags))) to bResult