Possible to capture ComboBox "DroppingDown" event? - c#

I have a System.Windows.Forms.ComboBox on a form and I want to capture the event just before the ComboBox's menu is displayed (something like "DroppingDown"). I can't seem to find a suitable event.
Is capturing this type of event possible with a ComboBox?

The ComboBox should have a DropDown Event. If I am not mistaken, this event should fire immediately when the drop down list starts to show.
What exactly are you wanting to accomplish immediately before the drop down shows that necessitates your capturing of such an event?

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Don't have Click event in TextBox in WPF C#

I just want to add simple thing, wherever i click on TextBox I want to delete text that is inside. The thing is I DON'T have in list of events, event called Click.. Is this even possible? Or just I need to install some add on. Buttons are fine, they have Click event.
MouseButtonLeftUp would work if you only are concerned with mouse clicks. With that said, what if someone tabs into the box or focus is entered by other means?
At that point you may want to look at the GotFocus event. Any time the TextBox receives focus, you can handle the event.
TextBox has events called MouseLeftButtonUp and MouseLeftButtonDown, you can use them.

ComboBox event trigger happening even when user doesn't select item

I need to catch an event when a user selects an item from a combo box. After reading some answers here on StackOverflow I used this method
(XAML):
SelectionChanged="LocationBox_SelectionChanged"
And the event handler in C#:
private void LocationBox_SelectionChanged(object sender, SelectionChangedEventArgs e)
The problem is that this event handler is getting tripped numerous times as the ComboBox is being built dynamically and not when a user selects an item. By the way, this method does work correctly when a user selects an item. The problem is all of these extraneous events.
I want the event handler to be called only when a user selects an item from the combobox. I do not want the event handler to be called when the combobox is being built dynamically before it is displayed. It appears that every time an item is added to the combobox it is tripping the event handler. I want the event handler to be tripped IFF a human being makes a selection from the combobox.
Suggestions? Thanks.
Unsure about the selectionChanged signal.
You can always use QObject: blockSignals during QComboBox editing?
It's a problem because when it falsely reports a user event my code would like to do something with the user selected index. However, since the user didn't actually select anything the event, and subsequent index, is wrong causing a crash.
Just return from your event handler immediately in case SelectedItem == null or SelectedIndex == -1.

Column of a selected row in Listview in Selectionchanged event handler

this is very easy question but all web solution i found didn't work
is it good to use selection changed event i want event to fire only when i mouse click on row, otherwise i can scroll through all list ?
I never tested but i think you can use a simple RelayCommand with the event "Click" to manage this.

SelectedIndexChanges fires before TextChanged event

I have a grid which contains multiple columns/rows with ASP TextBox controls. In addition to this, above the grid I have a radio button list which contains years.
The user can enter numbers into the TextBoxes and then click an item on the RadioButton list to save the information then switch years or click an update button to just save the information and remain viewing the data.
If I click the 'save' button the textchanged event handler fires and I know what rows on my grid had something changed, then I update my DB and then get the data again to display to the user.
If however I click the radiobuttonlist to switch years the SelectedIndexChanged event fires but the TextChanged event handler does not run because the save and get data runs first, rebinding the grid and eventhandler.
This appears to me to be something to do with the way events run in .net, does anyone know how can I get the textchanged event handler to run first when clicking a radio button list?
I'm using VS2005, .Net 2.5, ASP.Net, C#
Thanks in advance
Your question is not clear. Anyway i can understand that you have problem with the event handlers and how they are called.
I want to know what is the need of calling the textchanged event and SelectedIndexChanged. Even they are not called your data would be get saved perfectly.

C# Datagridview SelectionChanged Event fires earlier than I want it to

I'm working with Windows forms. I want an event to fire when the user makes a selection of cells (or one cell) in the datagridview. The SelectionChanged Event is firing as soon as I select one cell. Is there any way to have it wait for the user to be done selecting?
I have tried the CellMouseUp event, but I don't like its behaviour because if MouseUp happens outside the grid it doesn't fire.
As they select each cell a new selection change should be fired. so you are looking at "remembering" the selected cells each time the eventhandler gets triggered and then doing your processing based on that.
How much of a pain this going to be depends on what processing you are doing with the selection. Could be a good deal.

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