DBGrid1.Columns[0].Width:= .... / geht das auch automatisch?

[Delphi.Narium]

Naja, dann machen wir mal weiter und ergänzen die Routine:

Delphi-Quellcode:

  for i := 0 to DBGrid1.Columns.Count - 1 do
  begin
    case DBGrid1.Columns[i].Field.DataType of
      ftString, ftWideString : 
      begin
        DBGrid1.Columns[i].Width := DBGrid1.Canvas.TextWidth(DBGrid1.Columns[i].Field.AsString);
        DBGrid1.Columns[i].Alignment := taLeftJustify;
      end;
      ftSmallint, ftInteger, ftWord, ftAutoInc, ftLargeint : 
      begin
        DBGrid1.Columns[i].Width := DBGrid1.Canvas.TextWidth(Format('%6.0n',[DBGrid1.Columns[i].Field.AsFloat]));
        DBGrid1.Columns[i].Alignment := taRightJustify;
      end;
      ftFloat, ftCurrency : 
      begin
        DBGrid1.Columns[i].Width := DBGrid1.Canvas.TextWidth(Format('%6.2n',[DBGrid1.Columns[i].Field.AsFloat]));
        DBGrid1.Columns[i].Alignment := taRightJustify;
      end;
      ftDate : 
      begin
        DBGrid1.Columns[i].Width := DBGrid1.Canvas.TextWidth(FormatDateTime('dd.mm:yyyy', DBGrid1.Columns[i].Field.AsDateTime]));
        DBGrid1.Columns[i].Alignment := taLeftJustify;
      end;
      ftTime : 
      begin
        DBGrid1.Columns[i].Width := DBGrid1.Canvas.TextWidth(FormatDateTime('hh:nn:ss', DBGrid1.Columns[i].Field.AsDateTime]));
        DBGrid1.Columns[i].Alignment := taLeftJustify;
      end;
      ftDateTime : 
      begin
        DBGrid1.Columns[i].Width := DBGrid1.Canvas.TextWidth(FormatDateTime('dd.mm.yyyy hh:nn:ss', DBGrid1.Columns[i].Field.AsDateTime]));    
        DBGrid1.Columns[i].Alignment := taLeftJustify;
      end;
    else
      DBGrid1.Columns[i].Width := DBGrid1.Canvas.TextWidth(DBGrid1.Columns[i].Field.AsString);    
      DBGrid1.Columns[i].Alignment := taCenter;
    end;
  end;

Achso: Das ist jetzt einfach nur ungetestet hingedaddelt.
Bei den Format- bzw. FormatDateTimeaufrufen kannst Du die Formatstrings ja entsprechend Deinen Wünschen anpassen, ebenso die rechts- oder linksbündige Ausgabe ...