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unit splitfns;
interface
uses Classes, Sysutils;
function GetNextToken(Const S: string; Separator: TSysCharSet; var StartPos: integer): String;
{Returns the next token (substring) from string S, starting at index StartPos and ending 1 character
before the next occurrence of Separator (or at the end of S, whichever comes first).}
{StartPos returns the starting position for the next token, 1 more than the position in S of
the end of this token}
procedure Split(const S: String; Separator: TSysCharSet; MyStringList: TStringList);
{Splits a string containing designated separators into tokens and adds them to MyStringList NOTE: MyStringList must be Created before being passed to this procedure and Freed after use}
function AddToken (const aToken, S: String; Separator: Char; StringLimit: integer): String;
{Used to join 2 strings with a separator character between them and can be used in a Join function}
{The StringLimit parameter prevents the length of the Result String from exceeding a preset maximum}
implementation
function GetNextToken(Const S: string; Separator: TSysCharSet; var StartPos: integer): String;
var Index: integer;
begin
Result := '';
{Step over repeated separators}
While (S[StartPos] in Separator) and (StartPos <= length(S)) do StartPos := StartPos + 1;
if StartPos > length(S) then Exit;
{Set Index to StartPos}
Index := StartPos;
{Find the next Separator}
While not (S[Index] in Separator) and (Index <= length(S))do Index := Index + 1;
{Copy the token to the Result}
Result := Copy(S, StartPos, Index - StartPos);
{SetStartPos to next Character after the Separator}
StartPos := Index + 1;
end;
procedure Split(const S: String; Separator: TSysCharSet; MyStringList: TStringList);
var Start: integer;
begin
Start := 1;
While Start <= Length(S) do MyStringList.Add(GetNextToken(S, Separator, Start));
end;
function AddToken (const aToken, S: String; Separator: Char; StringLimit: integer): String;
begin
if Length(aToken) + Length(S) < StringLimit then
begin
{Add a separator unless the Result string is empty}
if S = '' then Result := '' else Result := S + Separator;
{Add the token}
Result := Result + aToken;
end
else
{if the StringLimit would be
exceeded, raise an exception}
Raise Exception.Create('Cannot add token');
end;
end.
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