Parsing and Try APIs
Prefer a Try... API when malformed input is expected. It makes failure a normal branch instead of silently turning an error into an empty value.
if TStringKit.TryHexDecode(Input, Value) then
begin
Writeln(Value);
end;Strict functions
| Function | Accepts | Failure result |
|---|---|---|
TryHexDecode | an even number of hexadecimal characters | False; decoded string is cleared |
TryDecode64 | standard padded Base64; whitespace is ignored | False; decoded string is cleared |
TryFromRoman | canonical Roman numerals from 1 to 3999 | False; integer value is set to 0 |
The successful paths are demonstrated by the compiled hex, Base64, and Roman numeral recipes.
The older HexDecode, Decode64, and FromRoman methods remain for compatibility. Their failure behaviour is deliberately different: HexDecode is permissive, Decode64 returns an empty string on invalid input, and FromRoman remains permissive. Do not use their result alone to distinguish an invalid value from a valid empty one.