Is there a way to know if a Windows Form is closing?
I would have to know from another class with a reference to the windows form. Something like:
if WinForm.IsClosing then ....
How about using the event Form.FormClosing Event
The FormClosing event occurs as the form is being closed. When a form
is closed, it is disposed, releasing all resources associated with the
form. If you cancel this event, the form remains opened. To cancel the
closure of a form, set the Cancel property of the FormClosingEventArgs
passed to your event handler to true.
Related
I've got a TreeView which acts as the main way of navigating a WPF application.
When the user selects a new item in the TreeView if the page they're leaving has unsaved information we offer the chance to cancel the move to continue working on the current data/save it. This currently happens in the PreviewMouseDown event handler.
It seems however that throwing up a dialog that offers a yes/no/cancel option here prevents the SelectedItemChanged event from ever actually firing, I assume because another mouse click has occured. As a result, if they decline the option to stay on the current page, it's still not changing.
Is there any way to re-fire the event from within PreviewMouseDown so that the SelectedItemChanged event still gets called?
Is there any way to re-fire the event from within PreviewMouseDown so that the SelectedItemChanged event still gets called?
It would be easier to call the event handler manually just as you would call a method. Or better yet, break out the code in the event handler to a standalone method that you call from both the PreviewMouseDown handler and the SelectedItemChanged handler.
The other option would be to change the SelectedItem or IsSelected property so the event fires again.
Hi I have main form in which I am displaying user controls like ManageDepartment. I have few buttons like RESET in main form.
I want to have event in ManageDepartment to reset controls.
When user clicks on Reset Button on main form, the button should call the reset event on displayed control i.e. ManageDepartment
Can any one suggest me how can I achieve this?
If this is duplicate question, please direct me to original question.
You don't call an event. If the user control has a Reset event then that event would get raised by that control.
It sounds more like what you need is a Reset method on the user control. You would handle the Click event of the Button on the form and call the Reset method of the control. In that method you would do as required to reset the control, e.g. call Clear on each TextBox.
I have a form that has a WebBrowser control. Onload, it navigates to some URL.
On DocumentCompleted event handler, after getting the needed data the form is closed. This works most of the time, but sometime it pops up an IE window w/ the same URL after the form has already closed.
I noticed that in DebugView, it logs m_useSurfacePresenter 1. When this gets logged before the Close() is called, there is no popup. But when this gets logged after the Close() is called, then the popup appears.
You need to check the JavaScript .onunload event in that document, if it is set to open a new window (browser) when that page is unloading, then it will be triggered when you close your winform which is hosting the webbrowser control, and in turn, the page.
So, when you close the winform, the page's onUnload event in the webbrowser control will also be triggered as a result due to the way the events are chained in a Document/Page --> WB Control --> WinForms Form setup.
You can actually set this to nothing, by running a particular JS command directed to the page in the WB control, you can set the .OnUnload event to "function () {};", which will ensure whatever it is set to will be turned into Nothing/Null. Here is a code example:
window.onunload = function () { };
Let me know how it goes, and I will help you out if that doesn't fix it. Notice the above is JS, and there are ways to execute JS directly from teh WB Control, many examples on the web, there are actually 2 ways, one using .execScript and another one using the newer method, which is .InvokeScript.
What's the name of the default red button with an X in the middle at the top right?
EDIT: I want to get the event associated with clicking that button.
You cannot disable the close box on its own using in properties window like you can with the minimize and maximize boxes. You can however disable the control box which contains them all.
Setting ControlBox to false will remove the minimize, maximize and close buttons.
You might want to consider why you are doing this though, as it's generally a good idea to let users quit out of windows using the close button (think of it as a cancel button).
EDIT:
You can handle when the user clicks on that close button using either the Closing or the Closed events of the Form. The difference between the two is that the Closing event fires before the form has closed (meaning that you can veto the closure by setting the Cancel property of the FormClosingEventArgs to true), whereas the Closed event fires after the form has actually closed.
it is possible to hook all messages goes to a form by implementing ImessageFilter interface
this link can be use full Using IMessageFilter to create a generic filter for operating system events
You can disable it by setting the ControlBox to false in the form properties, or in code like the following:
this.ControlBox = false;
Setting this will also hide the minimize and maximize buttons if that is OK. If not, the solution is a bit more elaborate.
i have a windows form that inherites from another windows form in the same project,
the problem is when i click a button in the inherited form the eventhandler fires twice
performing the event in the parent form and then performs the event in the inherited form
.
any suggestions?
http://www.metacafe.com/watch/852308/inheritied_forms_c/
in this video u will see what am doing exactly and the problem am facing is in the end of this video .. u will see exactly what i mean –
This is the way it's supposed to work. You have two event handlers, both are executed. I would suggest the following:
In the parent form, add a method
Protected Overridable Sub OnOKButtonClick()
MsgBox("Parent Form OK Button Clicked")
End Sub
which you call from the button's click event. In the inherited form, remove the button click event handler, and override the OnButtonClick method
Protected Overrides Sub OnOKButtonClick()
MsgBox("Inherited Form OK Button Clicked")
End Sub
This should accomplish what you are after.