Как получить доступ к определенной части GUID?

{ Manchmal wird nur ein Teil einer GUID benotigt.... }
 { You maybe have to access  just a part of a GUID. }
 
 
 { Const for the function Format(...) }
 const
   fsGUID: string = 'D1: $%s'#13#10'D2: $%s'#13#10'D3: $%s'#13#10     +
     'D4: $%s $%s $%s $%s $%s $%s $%s $%s';
   fsGUIDParts: string = 'D%d:%s';
 
   // Type for the GUID part to be shown 
type
 
   TGUIDPART = (guidp_NoFormat, guidp_All, guidp_D1,
     guidp_D2, guidp_D3, guidp_D4);
 
 { This GUIDToStringEx function give you the full GUID string 
  according with then format string FStr (you can change it !!!) }
 function GUIDToStringEx(Guid: TGuid; FStr: string): string; overload;
 begin
   Result := Format(FStr,
     [IntToHex(GUID.D1, 8),
     IntToHex(GUID.D2, 4),
     IntToHex(GUID.D3, 4),
     IntToHex(GUID.D4[0], 2),
     IntToHex(GUID.D4[1], 2),
     IntToHex(GUID.D4[2], 2),
     IntToHex(GUID.D4[3], 2),
     IntToHex(GUID.D4[4], 2),
     IntToHex(GUID.D4[5], 2),
     IntToHex(GUID.D4[6], 2),
     IntToHex(GUID.D4[7], 2)
     ]);
 end;
 
 { This GUIDToStringEx function give you the part of the GUID 
  to be shown, according to the part type GUIDPart }
 function GUIDToStringEx(Guid: TGuid; Part: TGUIDPART): string; overload;
 var
   i: Integer;
   S: string;
 begin
   S := '';
   case Part of
     guidp_NoFormat: S := GUIDToString(Guid);
     guidp_All:      S := GUIDToStringEx(Guid, fsGUID);
     guidp_D1:       S := Format(fsGUIDParts, [1, ' $' + IntToHex(GUID.D1, 8)]);
     guidp_D2:       S := Format(fsGUIDParts, [2, ' $' + IntToHex(GUID.D2, 4)]);
     guidp_D3:       S := Format(fsGUIDParts, [3, ' $' + IntToHex(GUID.D3, 4)]);
     guidp_D4:
        begin
         for i := 0 to 7 do S := S + ' $' + IntToHex(GUID.D4[i], 2);
         S := Format(fsGUIDParts, [4, S]);
       end;
     else
        S := '?';
   end;
   Result := S;
 end;
 
 { How to use the different GUIDToStringEx functions }
 
 procedure TForm1.Button1Click(Sender: TObject);
 var
   NewGUID: TGUID;
 begin
   { Create a new GUID }
   NewGUID := StringToGUID(CreateClassID);
 
   { Standard formated GUID string }
   label1.Caption := GUIDToStringEx(NewGUID, guidp_NoFormat) +
     #13#10+
 
    { Full formated GUID string acc. with fsGUID}
     GUIDToStringEx(NewGUID, fsGUID) +
     #13#10+
 
    { Full formated GUID string with default formating}
     GUIDToStringEx(NewGUID, guidp_All) +
     #13#10+
 
    { Part D3 of the GUID only }
     GUIDToStringEx(NewGUID, guidp_D3);
 end;

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