Validating issue TextBox & TabControl

[egmano]

Hi,

I am having a validation issue with the TextBox placed in a TabControl.

(1) Draw a TabControl and place a one or more Text box in the TabPage 1.
(ii) Textbox_validating event check if the textbox is empty Prompt some message and set the focus to the same textbox.
(iii) Run the project project click on the textbox then press tab it will propmpt the message and focus ramins in the textbox

Now
(iv) Click on the other TabPage

Now the Message prompting Twice and the Control moves to other TabPage

How to fix this issue?

Regards
Mano