Author: Jonas Bilinkevicius

How can I change the language driver of a Paradox table at runtime?

Answer:

The following code should to that:

1   procedure SetLanguage(Tbl: TTable; Lang: DbiName);
2   var
3     pOptDesc: pFLDDesc;
4     pOptData: pBYTE;
5     hDb: hDbiDb;
6     TblDesc: CRTblDesc;
7     Dir: string;
8   begin
9     pOptDesc := AllocMem(sizeof(FLDDesc));
10    pOptData := AllocMem(20);
11    SetLength(Dir, dbiMaxNameLen + 1);
12    Tbl.Active := True;
13    Check(DbiGetDirectory(Tbl.DBHandle, False, PChar(Dir)));
14    SetLength(Dir, StrLen(PChar(Dir)));
15    try
16      FillChar(TblDesc, sizeof(CRTblDesc), #0);
17      Tbl.DisableControls;
18      Tbl.Close;
19      Check(DbiOpenDatabase(nil, nil, dbiReadWrite, dbiOpenExcl, nil, 0, nil, nil,
20        hDb));
21      Check(DbiSetDirectory(hDb, PChar(Dir)));
22      pOptDesc.iOffset := 0;
23      pOptDesc.iLen := Length(Lang) + 1;
24      StrPCopy(pOptDesc.szName, 'LANGDRIVER');
25      StrPCopy(PChar(pOptData), Lang);
26      TblDesc.iOptParams := 1;
27      TblDesc.pfldOptParams := pOptDesc;
28      TblDesc.pOptData := pOptData;
29      StrPCopy(TblDesc.szTblName, Tbl.TableName);
30      StrCopy(TblDesc.szTblType, szParadox);
31      Check(DbiDoRestructure(hDb, 1, @TblDesc, nil, nil, nil, False));
32    finally
33      Check(DbiCloseDatabase(hDb));
34      FreeMem(pOptDesc, sizeof(FLDDesc));
35      FreeMem(pOptData, 20);
36      Tbl.EnableControls;
37    end;
38  end;