他们是在使用另一个 combobox 后禁用 combobox 的方法吗？ vb.net

Question

So I am making a simple register system and I am using 3 ComboBox and I want to know if their is a way to disable the 2 other ComboBox if I selected an item from 1 ComboBox?

Answer 1

You can set the Enabled property to False on the other two combo boxes in the SelectedIndexChanged event. Just make sure that the SelectedItem property of your combo box is not null before disabling the other two:

Private Sub ComboBox1_SelectedIndexChanged(sender As Object, e As EventArgs) Handles ComboBox1.SelectedIndexChanged
    If ComboBox1.SelectedItem IsNot Nothing Then
        ComboBox2.SelectedItem = Nothing
        ComboBox2.Enabled = False
        
        ComboBox3.SelectedItem = Nothing
        ComboBox3.Enabled = False
    End If
End Sub