short question: What's better?
Form KeyDown event vb Private Sub MainForm_KeyDown(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyEventArgs) Handles Me.KeyDown End Sub
Override OnKeyDown
vb Protected Overrides Sub OnKeyDown(ByVal e As System.Windows.Forms.KeyEventArgs) MyBase.OnKeyDown(e) End Sub
I'm trying to validate a few things in a form I'm building. It has a datagrid with clients info (taken from an access database) and a few textboxes where the user can type some search criteria. The thing is that those same textboxes are used to add new clients to the database and to modify a client's information if one from the datagrid is selected, so I made it that the buttons to insert and modify clients are disabled on load and thenevery time the text on a textbox changes ("TextChanged" event) they become enabled. So far so good. But then I wanted to make it so when a client from the datagrid is selected both buttons become disabled again until the text on a textbox changes (to make sure they're adding a different client and not the same one that was
selected).
I tried using the CellClick event from the datagrid to disable the buttons, but since every time a client is selected from the datagrid the info is shown on the textboxes, this triggers the TextChanged event too, and the buttons become available.So, is there a way I can tell the TextChanged event not to be triggered when the CellClick event occurs?
Is it possible to set focus on the keydown event so after the button control, sets the focus into the keydown? although says often control can have focus,.Putting a button and a keydown event on a form...
View 2 RepliesProgramming language is vb.net
View 1 RepliesI have this code in the onKeyDown event of the datagridview.
Private Sub DataGridView1_KeyDown(ByVal sender As System.Object, ByVal e As System.Windows.Forms.KeyEventArgs) Handles DataGridView1.KeyDown
Select Case e.KeyCode[code]....
This works. When the Enter button is pressed, it acts as the TAB button.The problem I am having is this only works if the datagridviewer is selected.As soon as I enter data into a cell (A cell is selected) the code wont work as it is not set for the cell keyDown event. The event does not exist, so I have to somehow create it.
I have a WinForms application (OwnerForm) with some UserControl. When textbox of UserControl is changed, I want to filter content of a OwnerForm. But how can I make it? I don't want to specify OwnerForm inside the user control. I know a solution to add manually handlers for MyUserControl.tb.TextChanged to some functions on a owner form, but I think it's bad way. I'll prefer to have overridable functions, but I can't imagine how to do it.
View 5 RepliesI would like to shadow/override an event in VB.NET v2
I need to do it, because I need to implement a interface, let's name it IVisibleChanged, on the custom objects that does not have defined this event, and on the objects that already have defined this event (custom Button, by eg.)[code]...
I would like to shadow/override an event in VB.NET. I do it only because I have to implement in this object an interface, that contains the same event like the base object itself, and I need to keep this base event as is it without modification nor supplementary event additions.How can I do it?
Public Shadows Event VisibleChanged As EventHandler Implements IVisibleChanged
So, I would like to implement a interface that contains VisibleChanged event, but to keep functional the myBase VisibleChanged event too.
[code].....
this code works
Private Sub TxtLname_KeyDown(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyEventArgs) Handles TxtLname.KeyDown
If e.KeyCode = Keys.Enter Then
If IsNumeric(TxtLname.Text) Then[code]....
when I replace the keys.enter with "keys.tab" it won't work..
Private Sub TxtLname_KeyDown(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyEventArgs) Handles TxtLname.KeyDown
If e.KeyCode = Keys.tab Then
If IsNumeric(TxtLname.Text) Then[code].....
my child form is a game that allows user to move using keydown event (arrow key left and right). But when i import it to MDI, keydown event doesn't work anymore. Am i missing something here?
View 3 Replieshow to use the keydown event soif you press 'A' a messagebox will popup saying you pressed A else it will say This function is not reconised i am hoping to use this knowlage to start a game so that if you press W the image will go up.
View 8 RepliesI have this code that's suppose to override the form closing event, It fires off sucessfully however doesn't prevent the form from closing.
Private Sub Form_Close(ByVal sender As Object, ByVal e As System.ComponentModel.CancelEventArgs) Handles MyBase.Closing
Me.Hide()
e.Cancel = True
End Sub
Ok, I've been searching all over the web for an answer to this and I'm getting nowhere. I've found several examples and tried code translators, but they either fail to compile at all (syntax is wrong) or fail to solve the problem. Here is what I am up against:
I am trying to implement a service object class for the POS for .NET library using VB9. Specifically, the BillDispenser class. I define my class and inherit from Microsoft.PointOfService.BillDispenser. As normal, it creates stubs for all the MustOverride (abstract) properties and methods that I need to override (I love that), EXCEPT for the DirectIOEvent. Apparently this event is defined as abstract in the POSCommon base class, but VB doesn't generate a stub for it.
No compile errors are generated from not defining it, but I get the following runtime error as soon as my unit test attempts to load the dll[code]...
why does the keydown event not responding when i put a button on the form?all are set but after i put one button keydown event is not working...
View 9 Repliesin my Application i have created a status strip which has three lable to show capslock status, numlock status and current date.I have used the following code, it is working perfectly when Master(MDI Parent) Load but it dosen't change when key is pressed. every time i start my application it shows the current status of the keys but dosent change when key is pressed.[code]
View 1 RepliesThis simple code works at child form, but not at MDI form.
Is there anything should I add or change?[code]...
I have checked my code countless times, tried other computers, and yet the keydown event will not work.
My code:Private Sub Form_KeyDown(KeyCode As Integer, Shift As Integer)
If KeyCode = vbKeyRight Then
imgPerson.Left = imgPerson.Left + 500
End If
End Sub
That's all there is because I was just testing it out. imgPerson does exist, so that's not a problem.
if I press F1 on another program like, internet explorer, it will open music. When I press F1 on my Windows Form(My program), It work fine and it play my music but when i'm on internet explorer or anything else it doesn't work and I am wondering if I can.
View 7 RepliesI'm using ASP.Net 2.0. I have a custom control that is inherits from a 3rd-party vendor's control. I'm trying to override the Render method. [code] What I need is that under certain situations I want to be able to render a Button instead of the original control.But I want the Button to have the same client Id as the control so that I can use javascript to manipulate it.How do I assign a clientid to the button?
View 1 RepliesWhen editing vb.net forms code in vs2008, how do I select base class events that I want to override? In vs2003 there was a list of overridables in the drop down list but now that list is missing?
View 4 RepliesI have to two forms. Form one has several check boxes and when a button is pressed, a second form is opened and certain functions are ran based on which check boxes are selected.The problem is that the second form doesn't show until all of the functions are done.I decided to use the Form's Activated event, which works fine. However, the event fires every time the form comes into focus.Is there anyway to override the event and make it only fire once?
View 1 RepliesBasically, what I want to do is create a new control called EncryptedPictureBox. The image path I would be loading into ImageLocation would be the path of a 512 bit encrypted image. Normally if I load this type of file, it will not display. So I want to override Load() so that I can write the encrypted image to a stream, decrypt it, and then display the stream. I'm trying to save processing time so I don't have to grab the encrypted image, save it to disk as a decrypted image, then display it, then when done, delete the decrypted image from disk.
View 11 RepliesCorrect me if i'm wrong, but i believe most (if not all) classes in the CLR that raise events raise those events from protected methods, for example Form.OnMouseDown... so... In a subclass, when would you want to override the "OnXyzMethod" instead of simple adding an event handler like Visual Studio does by default when you want to handle a controls event?
View 2 RepliesAt the moment I have the following Command class:
Public Class SubscribeCommand
Implements ICommand
Private ReadOnly _vm As MainWindowViewModel
Public Sub New(ByVal vm As MainWindowViewModel)
_vm = vm
End Sub
[Code]...
In a tutorial i read, you have to implement add {} and remove {} for the canExecuteChanged-Event. But how can i do that, with vb.net?
I am running VS 2008 and building my app on a Windows 7 box. The main form/window has a KeyDown event handler as follows in it:
Private Sub Form1_KeyDown(ByVal sender As System.Object, ByVal e As System.Windows.Forms.KeyEventArgs) Handles MyBase.KeyDown
MsgBox("control = " + e.Control.ToString + ", shift = " + e.Shift.ToString + ", e.Keycode = " + e.KeyCode.ToString)
When I build it and run it within VS it seems to run fine. The messagebox appears with the state of the control and shift keys along with the key code of the key I pressed. However, if I take the executable and run it on an XP box (both using .Net Runtime 3.5) as soon as the main form opens, the messagebox appears. Basically the "KeyDown" event seems to be firing without any keys being pressed. The messagebox comes back with: "control = False, shift = False, e.Keycode = None".
How is this possible? How can the keyDown event be fired when no keys have been pressed (as is confirmed by the output contained in the messagebox?) how I can diagnose this on the XP box since it does not have Visual Studio on it?Update I tried creating a brand new project where there is only "form1" and the only code behind this is the keyDown event handler. It just opens a blank window and pops up the message box if a key is pressed. It worked as expected on the Win 7 box but when I moved the executable to the XP box, it immediately popped open the messagebox without pressing a key.
I need to make a simple yet cool program for my professor. The program is this: To get the program to work, the user first presses a button on the form. Then, when the user presses an up arrow on the keyboard, the cursor will change to a custom cursor (a cursor with an image of car {in .ico format} for example), when the user releases the up arrow key, the cursor turns back to default cursor -- which is arrow. When the user presses an up arrow and left arrow at the same time on the keyboard, then a different custom cursor will be shown instead of the default.
[Code]...
In my program I've used a text box and KeyPreview is True.When press the Enter-key i hope go to next row but called the default key?
View 2 RepliesHow do you read a key down event when your application is not focus but other are?
View 2 Repliesusing a datagridview and it bind by 3 rows and 3 columns,my task is when the press the F5 key then need to execute some code, my problem is if the datagridview cell is focused then now i press F5 key then the next task is executed but if the cursor is in the cell and i press F5 Key then the Key events was fired
View 1 RepliesHow can I get VB.net to work out that i have pressed +-*/ in Keydown events?
At the moment i am using a Select Case:
Select Case e.Key
'Numpad Numbers Keydown Events'
Case Key.NumPad0
Display.Append("0")
txtAnswer.Text = Display.ToString
Case Key.NumPad1
Display.Append("1")
txtAnswer.Text = Display.ToString
However, I can't find a key. thing to work with the numpad function buttons.
I tried using:
Case AscW(Chr(107))
Display.Append("+")
txtAnswer.Text = Display.ToString
But it didn't work,