combo box

Question

hi I have a combo box that is populated with a list of measurements and I would like to alter which items are shown depending on the users input ie; if they select the linear radio button the list is only populated with linear measurements. Can anyone help?

MythicalMe · Answer

It is easiest to use database tables but you can populate your 'detail' combobox (the one with the linear measurements) manually by capturing the first combobox's SelectedValueChanged event. Private Sub combobox1_SelectedIndexChanged(ByVal sender As Object ByVal e As System.EventArgs) Handles combobox1.SelectedValueChanged dim value as string = combobox1.value ' this assumes the value is string type combobox2.items.clear ' now iterate through your data and add the measurements End Sub

squidge1980 · Answer

Thanks! Will it work in the same way if populating the combo box from another combo box? For example having a list of types such as linear and when linear is selected only linear measurements are displayed in the 2nd combo box? I have tried searching for ways to accomplish this but all answers seem to point to using database tables to populate the combo boxes and then assigning relaionships...Is there another way?

MythicalMe · Answer

I can think of a dozen ways to accomplish this task but in the end what you're probably going to end up doing is capturing the radio button's check changed event and loading the combo box accordingly. The combo box is a fairly simple control in that it displays whatever you put into it. Be careful about capturing the check changed event and reading data. The control compenents are initialized before the page_load event occurs. This means that if the default for the radio button is checked that the initializataion will generate a checkchanged event. If your data hasn't yet been initialized then an error will be generated before page load. This has the nasty result of giving no debug references. To avoid this I usually have an initialization flag that I set to False until the page has been loaded.