Dim flag as Boolean = False

Private Sub ComboBox1_SelectedValueChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles ComboBox1.SelectedValueChanged
	If me.flag Then
	    Try
	        MsgBox(Me.ComboBox1.SelectedValue)
	    Catch exe As Exception
	        MsgBox(exe.Message)
	    End Try
	End If
End Sub

Private Sub Button1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button1.Click
	Me.flag = False
	Me.SqlDataAdapter1.Fill(DataSet11, "Categories")
	Me.ComboBox1.DataSource = DataSet11.Tables("Categories")
	Console.WriteLine("categories")
	Me.ComboBox1.ValueMember = "CategoryID"
	Console.WriteLine("value")
	Me.ComboBox1.DisplayMember = "CategoryName"
	Console.WriteLine("display")
	Me.flag = True
End Sub

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