How to Use TABs in a VB Text Box Without Changing the Focus

- Standard and Professional Editions of Microsoft Visual Basic for

  Windows, version 3.0

SUMMARY

This article shows by example how to use the TAB keypress within a control, such as a text box. Normally, the TAB key causes the focus to move away from that control. The sample program in this article shows you how to change this behavior so you can use the TABs within a text box.

The sample program does this by setting the TabStop property of all controls on the form to False when the text box has the focus. Tabbing changes focus between any controls which have a TabStop property equal to True, which is the default. When the TabStop property is true for one or more controls on a form, Visual Basic does not allow tabs to be entered directly into a control.

MORE INFORMATION

Step-by-Step Example

In the example below, the Text2 box will accept and hold TAB keystrokes, keeping them in the Text property along with the other entered characters. The Text1 and Text3 boxes will not accept TAB keystrokes. When Text1 and Text3 have the focus, pressing the TAB key changes the focus to the next control in the tab order.

1. Start a new project in Visual Basic. Form1 is created by default.

2. Add three text boxes (Text1, Text2, and Text3) to Form1. Select the Text2 box and press the F4 key to display the Properties window. Set the MultiLine property of Text2 to True.

   NOTE: When you press the TAB key, single-line text boxes beep and do not accept the TAB keystroke, but multiLine text boxes do accept TAB keystrokes.

3. Double-click the Text2 box to open the code window. Choose the GotFocus event from the Proc box. Add the following code to the Text2 GotFocus event:

      Sub Text2_GotFocus ()
         ' When Text2 gets the focus, clear all TabStop properties on all
         ' controls on the form. Ignore all errors, in case a control does
         ' not have the TabStop property.
         On Error Resume Next
         For i = 0 To Controls.Count - 1   ' Use the Controls collection
            Controls(i).TabStop = False
         Next
      End Sub
   
      NOTE: See the "Controls Collection" section below for an explanation of
      the Controls collection.
   
   

4. Choose the LostFocus event from the Proc box. Add the following code to the Text2 LostFocus event:

      Sub Text2_LostFocus ()
         ' When Text2 loses the focus, make the TabStop property True for all
         ' controls on the form. That restores the ability to tab between
         ' controls. Ignore all errors, in case a control does not have the
         ' TabStop property.
         On Error Resume Next
         For i = 0 To Controls.Count - 1   ' Use the Controls collection
            Controls(i).TabStop = True
         Next
      End Sub
   
   

5. Start the program, or press the F5 key. Press the TAB key to give focus to Text2. Enter text into the Text2 box, pressing the TAB key as needed. Whenever Text1 or Text3 has the focus, pressing the TAB key moves the focus to the next control. Whenever Text2 has the focus, TAB keystrokes remain with the text in the text box. Close the form to end the program.

Tab Order

By default, Visual Basic assigns tab order to controls in the order you draw them on a form. Each new control is placed last in the tab order. You can control the order that controls gain focus in your application by changing the tab order at design time through the Properties window, or at run time through code.

To change tab order at design time:

1. Click a control to select it.

2. From the Properties window, select TabIndex. Visual Basic displays the current tab position in the Settings box.

3. Type the number for the tab order position you want the control to have.

4. Click the Enter button. You can test the tab order at design time by pressing Tab.

1. Click a control to select it.

2. From the Properties window, select TabStop. Visual Basic displays the current Boolean value in the Settings box.

3. Select True to designate the control as a tab stop, or select False to bypass the control in the tab order.

4. Click the Enter button.

A control whose TabStop property has been set to False maintains its position in the actual tab order as set by the TabIndex property, even though the control is skipped when you cycle through the controls by using the TAB key. If the TabStop property is False for all controls on the form, you can enter TAB keystrokes into MultiLine text boxes.

Controls Collection

The Controls collection is a collection whose elements represent each control on a form, including elements of control arrays. The Controls collection has a single property (Count) that specifies the number of elements in an array.

The Controls collection enumerates loaded controls on a form and is useful for iterating through them. The index in the syntax is between 0 and Controls.Count-1.

NOTE: Controls is a keyword but not a reserved word. It identifies an intrinsic form-level variable named Controls. If you omit the optional form reference, you must include the Controls keyword. If you include a form reference, you can omit the Controls keyword. For example, the following two lines have the same effect:

MyForm.Controls(6).Top = MyForm.Controls(5).Top + increment MyForm(6).Top = MyForm(5).Top + increment