You can put the focus on the following types of ASP.NET controls: Button, LinkButton, and ImageButton controls, CheckBox control, DropDownList control, FileUpload control, HyperLink control, ListBox control, RadioButton control, TextBox control.

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The following VB.NET code example shows how to set the focus on the control with the ID TextBox1:

Protected Sub Page_Load(ByVal sender As Object, _
    ByVal e As System.EventArgs)
End Sub