Is there any way to handle the Esc key event in Windows Forms?
Actually it is working fine when I put debugger in the code. Once I remove the debugger it is not getting fired.
What's the problem here?
If it is for a dialog then you can set the property CancelButton (of the form) to the button that cancels (e.g. named btnCancel and with text "Cancel" in a English language application.)
In this case you don't need to handle the key event for the Esc key.
you should add Form.KeyPreview = true in your Form.Designer.cs. And later you can use Form.KeyPress event.
Related
I'm trying to register a button press of the button F2 on the MC75a hand held terminal by Motorola/Zebra/Symbol. But it doesn't recognise the blue button press which is required to press F2. Any suggestions?
It depends on what is on your form. So if you have a windows form-project and a textbox is focused you could handle the keypress event of this control. If you have no focused controls, set your form to "keypreview = true". You can find this option in the settings of the form editor.
After enabling keypreview you can handle the keypress event from the form. This should work.
If you already enabled keypreview and it does not work, please make a test-form where you can see the keycodes which are send. There is a possibility to remap the keyboard of motorola devices.
I have a bug in my application that I don't know how to how to attack. Basically, key events "go missing" after some time. I have added event handlers to KeyDown, KeyPressed and KeyUp that write to the console (both for the Form and one of its TextBoxes). Here's the correct order of things:
control_PreviewKeyDown
ShellForm_KeyDown
control_KeyDown
ShellForm_KeyPress
control_KeyPress
ShellForm_KeyUp
control_KeyUp
In the failed state (which I can't reproduce consistently), I get these events when pressing a key (TextBox has focus):
ShellForm_KeyUp
control_KeyUp
Form.KeyPreview is true.
It's the same for all TextBoxes in the Form; they are not disabled and not set to readonly, but it's no longer possible to write text.
Problem is, I don't really know where to begin.
Begin with Application.AddMessageFilter(...) just to intercept the flow of events.
You can find some ideas here.
On Windows 7 Phone, using Silverlight framework
I'd like to handle when a Button is released.
It's easy to tell when the button is pressed (Click event which is fired either when pressed or when released according to the ClickMode property)
I've played with all the other events provided with the Events editor (KeyUp, LostFocus, MouseLeave etc..)
But I'm yet to find something that is definitive in regards to getting an event when a button is released.
Ultimately, I'm trying to handle doing a click vs a long click when pressing on a button
Thanks
For your situation, KeyUp is only half of the story. You also need to handle KeyDown where you will save the current time which you will then compare to the current time value after KeyUp to determine whether the press was short or long. You also need to make sure that you track one particular key in case your handler(s) is/are intercepting all key strokes.
If for some reason ClickDown/Up don't work out you could try handling the Click event but starting with a ClickMode of press, then changing ClickMode to release on the press handler. This process, though not simple, would give you a chance to implement the down-hold and timer-release sequence that you're looking for.
How can I capture the Keydown event of a form that is not active?
I found references to ProcessKeyDown but I couldn't find any help on that.
Please set KeyPreview of the form to true. First select form and press f4 key, it will open property window and their is KeyPreview and set it to true.
Right cilck on the form and cilck properties, then there will be flash button , it is for events for that object. Find thier Keypress event. just doulbe click on the column corresponding to that event. It will create event for keypress.
For the documentation and help, check this link.
Keypress events are only sent to Controls that have input focus. You can use the Control.HasFocus property to determine whether your Control has focus or not. Use the Control.Focus() method to give your control focus.
You can set a low level keyboard hook using SetWindowsHookEx() to listen for key press events.
If what you want to do is trigger some code in your program upon keys being pressed in the operating system regarding of whether the form is active or not then you can use the method described in this article:
Processing Global Mouse and Keyboard Hooks in C#
Here is a simple example of a program using that library to simulate a virtual mouse by pressing the numeric keys on the numpad.
'1'-'4' and '6'-'9' are directional keys, '5' is left click, '0' is double click.
Program.cs
Form1.cs
Observe that i didn't call the Application.Run(); with a new Form1() parameter so that the application would run but will not be visible on screen. To end the program you have to press CTRL+SHIFT+ESC, go to Processes page and end the process manually.
C# WinApps: the main form has a key binding to CTRL-V ...so anywhere in the main app when I press CTRL-V something runs..good ... but also there are some MDI apps that are opening inside this main app ... in one of those there is a test box...ah! now CTRL-V also has a meanining for text box which is "Paste" ... so I added PreViewKeyDown to textbox and handled it, so now it is pasting BUT it is ALSO doing the main CTRL-V key binding that I had defined for the whole app ... but I do no want this to happen.... what can I do? ( I cannot change the key binding od the main app. I must keep it.)
You need to register for the Control.KeyDown event and mark it as handled to prevent further propagation of the event.
e.Handled = true;