I have in my C# program textBox
I need that when the program start, the focus will be on the textBox
I try this on Form_Load:
MyTextBox.Focus
Textbox.Focus() "Tries" to set focus on the textbox element. In case of the element visibility is hidden for example, Focus() will not work. So make sure that your element is visible before calling Focus().
Textbox.Focus()
Focus()