Use up and down arrow keys to move to next edit box

The routine in the OnKeyDown handler (below) will build a list of the forms controls, and order them by TabOrder. It then walks the list to locate the next edit control int he desired direction. All you need to do it:

- Set the form's KeyPreview property to true.
- Add the following code and bind the Form's OnKeyDown event handler to the FormKeyDown procedure.


Russell

---

function SortControls(Item1, Item2: Pointer): Integer;
begin

  // Sort the controls by tab order
  result:=TWinControl(Item1).TabOrder - TWinControl(Item2).TabOrder;

end;

procedure TForm1.FormKeyDown(Sender: TObject; var Key: Word; Shift: TShiftState);
var  ctlEdit:       TEdit;
     listCtrls:     TList;
     dwSelf:        Integer;
     dwIndex:       Integer;
begin

  // Check key and active control
  if ((Key = VK_UP) or (Key = VK_DOWN)) and (ActiveControl is TEdit) then
  begin
     // Get current edit
     ctlEdit:=TEdit(ActiveControl);
     // Create list to hold all controls
     listCtrls:=TList.Create;
     // Resource protection
     try
        // Add all controls to list
        for dwIndex:=0 to Pred(ControlCount) do listCtrls.Add(Controls[dwIndex]);
        // Sort the list
        listCtrls.Sort(SortControls);
        // Locate the index of the control we are currently on
        dwSelf:=listCtrls.IndexOf(ctlEdit);
        // Clear the edit control pointer
        ctlEdit:=nil;
        // Now we either need to walk forwards or backwards, as well as implement wrap around
        if (Key = VK_DOWN) then
        begin
           // Walk from index plus one to end of list
           for dwIndex:=Succ(dwSelf) to Pred(listCtrls.Count) do
           begin
              // Check for edit type
              if (TWinControl(listCtrls[dwIndex]) is TEdit) then
              begin
                 // Found the next edit
                 ctlEdit:=TEdit(listCtrls[dwIndex]);
                 // Done processing
                 break;
              end;
           end;
           // Check edit
           if (ctlEdit = nil) then
           begin
              // Walk from start of list to current index
              for dwIndex:=0 to Pred(dwSelf) do
              begin
                 // Check for edit type
                 if (TWinControl(listCtrls[dwIndex]) is TEdit) then
                 begin
                    // Found the next edit
                    ctlEdit:=TEdit(listCtrls[dwIndex]);
                    // Done processing
                    break;
                 end;
              end;
           end;
        end
        else
        begin
           // Walk from index minus one to start of list
           for dwIndex:=Pred(dwSelf) downto 0 do
           begin
              // Check for edit type
              if (TWinControl(listCtrls[dwIndex]) is TEdit) then
              begin
                 // Found the next edit
                 ctlEdit:=TEdit(listCtrls[dwIndex]);
                 // Done processing
                 break;
              end;
           end;
           // Check edit
           if (ctlEdit = nil) then
           begin
              // Walk from end of list to current index plus one
              for dwIndex:=Pred(listCtrls.COunt) downto Succ(dwSelf) do
              begin
                 // Check for edit type
                 if (TWinControl(listCtrls[dwIndex]) is TEdit) then
                 begin
                    // Found the next edit
                    ctlEdit:=TEdit(listCtrls[dwIndex]);
                    // Done processing
                    break;
                 end;
              end;
           end;
        end;
        // If new edit is assigned then set focus
        if Assigned(ctlEdit) then ctlEdit.SetFocus;
     finally
        // Free the list
        listCtrls.Free;
     end;
  end;

end;