The tab order is the order in which a user moves focus from one control to another by pressing the TAB key. Each form has its own tab order. By default, the tab order is the same as the order in which you created the controls. Tab-order numbering begins with zero.
To set the tab order of a control
Additionally, by default, a GroupBox control has its own TabIndex value, which is a whole number. A GroupBox control itself cannot have focus at run time. Thus, each control within a GroupBox has its own decimal TabIndex value.
Finally, any control of the many on your form can be skipped in the tab order. Usually, pressing TAB successively at run time selects each control in the tab order. By setting the TabStop property, a control can be passed over in the tab order of the form.
To remove a control from the tab order
A control whose TabStop property has been set to false still maintains its position in the tab order, even though the control is skipped when you cycle through the controls with the TAB key.
Note A radio button group has a single tab stop at run time. The selected button (that is, the button with its Checked property set to true) has its TabStop property automatically set to true, while the other buttons have their TabStop property set to false. For more information about grouping RadioButton controls, see Grouping RadioButton Controls to Function As a Set.
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