If you are using VS, just doubleclick on the comboBox.
VS then creates the code needed to link things up and creates a routine "comboBox1_SelectedIndexChanged"that you'll need to edit to carry out the modifications to the form that you need. Otherwise, you'll need to manually add the changes obislavu talked about above.
SelectedIndexChanged is the default event. If you want to access other events, you can do so through by viewing the properties of the combobox. If you click on the events button on the properites form (a little lightning bolt) it will show you all the events that you can access....Doubleclicking any one will do the same process as above.
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