If input string can have spaces (which is shows malfunction somewhere in the system based on the base 64 encoded string shan't contain) then this character can appear anywhere and numbers of times in the string and they are must skipped.

That means "abcd", " abcd", "a bcd ", "a  bcd" and all permutation of 4 valid and ' ' (space) characters should be interpreted as a valid base64 encoded quartet. 

If this case valid the all of existing Decode function bleeding in several wounds.

In the eclrtl code I can't find any exception handling code (except of the CCompiledStrRegExpr class). Is this intentional based on resource demand, complexity or any other factor?