The .NET CF ComboBox doesn't have a DropDown event, so what's the alternative?

问题

I'm working on a .NET 3.5 SmartDevice project and I could really use the ComboBox DropDown event, but the .NET Compact Framework version doesn't have it. Is there another way to be made aware of when the list has dropped down?

回答1:

I use the GotFocus event to populate the combobox. I keep a boolean variable specifying wether the combobox is populated so it doesn't repopulate the combobox everytime it get's focus. it's a bit ugly, but it works...

回答2:

Why would you need to know when they dropped down the combo box? Usually you just need to know if they changed the value. Private Sub ComboBox1_SelectedValueChanged

来源：https://stackoverflow.com/questions/1105504/the-net-cf-combobox-doesnt-have-a-dropdown-event-so-whats-the-alternative