I took a break from porting code, and now I'm spending some more time on it again.
Problem is, I guess i'm still stuck backwards in my head (everything works fine on D6 :D).
Can anyone tell me why this simple code is not working?
if NewSig <> NewCompressionSignature then
E2015 Operator not applicable to this operand type
Here are the definitions of the above:
NewCompressionSignature: TCompressionSignature = 'DRM$IG01';
NewSig: array[0..SizeOf(NewCompressionSignature)-1] of Char;
I'm just guessing here because the type of TCompressionSignature is not given, but I can reproduce ERROR2015 if TCompressionSignature is declared as some kind of ShortString like
type
TCompressionSignature = String[8]
As you might know, Delphi is currently using Unicode as its standard internal string encoding. For backward compatibility reasons, the type ShortString and other short string types (like String[8]) were left unchanged. These strings have the same encoding like AnsiString and are composed of standard plain old 1-byte characters (AnsiChar).
NewSig on the other hand is composed of two-byte Unicode characters and can not be compared directly with an ShortString.
One solution of your problem would be to declare:
NewSig: array[0..SizeOf(NewCompressionSignature)-1] of AnsiChar;
Another solution would be be a cast to string:
if NewSig <> String(NewCompressionSignature) then ...
But I would prefer to change the array declaration if possible.
Please review the documentation short strings and about unicode - especially if you're doing io operations to ensure your input and output is read and written with the correct codepage.
