Returns a substring of a string.
function Copy(S: String; Index: Integer; Count: Integer): String;
Windows, Real, Protected
S is a string-type expression. Index and Count are integer-type expressions. Copy returns a string containing Count characters starting with the Indexth character in S.
If Index is larger than the length of S, Copy returns an empty string. If Count specifies more characters than remain starting at the Indexth position, only the remainder of the string is returned.