Validating textbox w/ Cancel button

[Darin]

I have a form w/ a textbox and Cancel button on it. I have a routine to
handle textbox.validat ing, and I have the form setup so the Cancel
button is the Cancel button.

WHen the user clicks on the cancel button, the textbox.validat ing is
being called. I don't want it to be since they are exiting the screen
the validation doesn't have to be done.

How can I do that.

Thanks.

Darin

*** Sent via Developersdex http://www.developersdex.com ***

[iwdu15]

RE: Validating textbox w/ Cancel button

if you want to exit the form when the user presses cancel then just say, in
the btnCancel click event

Me.Close()

and the form will close
--
-iwdu15

[Darin]

RE: Validating textbox w/ Cancel button

I know that, but the problem is when the user clicks EXIT, the
textbox.validat ing event is called BEFORE the cancel.click is done, so
the textbox is being validated. It doesn't need to be validated because
the user is exiting.

Darin

*** Sent via Developersdex http://www.developersdex.com ***

[Terry]

RE: Validating textbox w/ Cancel button

Yes, closing the form causes 'validating' to take place. One, remove the
"controlBox " from the form, so the user cant close it that way. Then in the
btnCancel_click event, either set a module level variable like mCanceling to
True and then in the validating event ... If not mCanceling ...
Another approach. in the btnCancel_Click event:
Removehandeler TextBox1.valida ting, Addressof TextBox1_Valida ting
--
Terry


"Darin" wrote:

I know that, but the problem is when the user clicks EXIT, the
textbox.validat ing event is called BEFORE the cancel.click is done, so
the textbox is being validated. It doesn't need to be validated because
the user is exiting.
>
Darin
>
*** Sent via Developersdex http://www.developersdex.com ***
>

[Al Reid]

Re: Validating textbox w/ Cancel button

"Terry" <Terry@nospam.n ospamwrote in message news:9059256D-E5C4-41D7-B702-667305E23EA4@mi crosoft.com...

Yes, closing the form causes 'validating' to take place. One, remove the
"controlBox " from the form, so the user cant close it that way. Then in the
btnCancel_click event, either set a module level variable like mCanceling to
True and then in the validating event ... If not mCanceling ...
Another approach. in the btnCancel_Click event:
Removehandeler TextBox1.valida ting, Addressof TextBox1_Valida ting
--
Terry
>
>

That doesn't work either, at least not for VB2005. I've been fighting the same problem for some time now. When you click on the
button the validating event fires. If you set e.Cancel=True the button events never fire.

I think that the only way to do this is to grab the mouse coordinates in the validating event, do a WindowFromPoint API call, then
compare the returned HWND to the Cancel Button's Handle. If the handle matched then immediately exit the Validating event without
setting e.Cancel = True.

--
Al Reid

[Terry]

Re: Validating textbox w/ Cancel button

Well it works for me - but one thing I left out - you need to set the cancel
buttons 'causes validation' to false. The following code works as you might
hope:
Public Class Form1
Private mCanceling As Boolean = False

Private Sub Button1_Click(B yVal sender As System.Object, ByVal e As
System.EventArg s) Handles Button1.Click
mCanceling = True
Me.Close()
End Sub

Private Sub TextBox1_Valida ting(ByVal sender As Object, ByVal e As
System.Componen tModel.CancelEv entArgs) Handles TextBox1.Valida ting
If Not mCanceling Then
If TextBox1.Text.L ength < 5 Then
e.Cancel = True
End If
End If
End Sub
End Class
The removehandeler method also works.

Also, as I just discovered, if you set the text box's causesvalidatio n to
false, you can close the form from the control box without validation taking
place. This really sounds more like a bug to me.

--


Terry


"Al Reid" wrote:

"Terry" <Terry@nospam.n ospamwrote in message news:9059256D-E5C4-41D7-B702-667305E23EA4@mi crosoft.com...

Yes, closing the form causes 'validating' to take place. One, remove the
"controlBox " from the form, so the user cant close it that way. Then in the
btnCancel_click event, either set a module level variable like mCanceling to
True and then in the validating event ... If not mCanceling ...
Another approach. in the btnCancel_Click event:
Removehandeler TextBox1.valida ting, Addressof TextBox1_Valida ting
--
Terry

>
That doesn't work either, at least not for VB2005. I've been fighting the same problem for some time now. When you click on the
button the validating event fires. If you set e.Cancel=True the button events never fire.
>
I think that the only way to do this is to grab the mouse coordinates in the validating event, do a WindowFromPoint API call, then
compare the returned HWND to the Cancel Button's Handle. If the handle matched then immediately exit the Validating event without
setting e.Cancel = True.
>
--
Al Reid
>
>
>

[Al Reid]

Re: Validating textbox w/ Cancel button

I had tried all of that, *BUT*, I had neglected to set the button's CausesValidatio n to False. DUH!!!
It does indeed work. I also got the WindowFromPoint approach working as well. Now I can go back and strip that out.

Thanks.

--
Al Reid (who didn't mean to hijack the thread)


"Terry" <Terry@nospam.n ospamwrote in message news:70E9A54F-85F3-49D4-AB1E-6EAFC54FCCE9@mi crosoft.com...

Well it works for me - but one thing I left out - you need to set the cancel
buttons 'causes validation' to false. The following code works as you might
hope:
Public Class Form1
Private mCanceling As Boolean = False
>
Private Sub Button1_Click(B yVal sender As System.Object, ByVal e As
System.EventArg s) Handles Button1.Click
mCanceling = True
Me.Close()
End Sub
>
Private Sub TextBox1_Valida ting(ByVal sender As Object, ByVal e As
System.Componen tModel.CancelEv entArgs) Handles TextBox1.Valida ting
If Not mCanceling Then
If TextBox1.Text.L ength < 5 Then
e.Cancel = True
End If
End If
End Sub
End Class
The removehandeler method also works.
>
Also, as I just discovered, if you set the text box's causesvalidatio n to
false, you can close the form from the control box without validation taking
place. This really sounds more like a bug to me.
>
--
>
>
Terry
>
>

[Darin]

Re: Validating textbox w/ Cancel button

That doesn't work for me. I am on VB.Net, VS 2003. When I click on the
cancel button it doesn't even get to the cancel.click event until AFTER
it has done the validating.

Private Sub Button1_Click(B yVal sender As System.Object, ByVal e As
System.EventArg s) Handles Button1.Click
MessageBox.Show ("Button1_click ")
mCanceling = True
Me.Close()
End Sub

Private Sub TextBox1_Valida ting(ByVal sender As Object, ByVal e As
System.Componen tModel.CancelEv entArgs) Handles TextBox1.Valida ting
If Not mCanceling Then
If TextBox1.Text.L ength < 5 Then
e.Cancel = True
End If
End If
End Sub

Run the program (make sure the tab stop has the textbox first then the
button), leave the text in textbox to be textbox, click on button, you
will see the message. Run it again, clear out the text in textbox, click
on cancel and you will not see the message - the system is not honoring
the cancel.click because (I guess) the e.cancel=true in _validating.


Darin

*** Sent via Developersdex http://www.developersdex.com ***

[Al Reid]

Re: Validating textbox w/ Cancel button

Just a follow-up. The thing that this approach does not allow (unless I've one again neglected the obvious) is using the escape key
to trigger the form cancel. If I hit the escape, the validation event fires and since the mCanceling is not True, the validation
error gets displayed before the form closes.

My final solution, unless someone has a better suggestion, is to change the Validating event to the Leave event and detecting
whether the cancel button had been clicked in the Leave event and exiting if it was. This way both the escape key and the cancel
button closes the form without causing the validation to occur.

The code to tell if the cancel button has been clicked is:

///////

Public Declare Function WindowFromPoint Lib "user32" (ByVal p As POINTAPI) As IntPtr

Public Structure POINTAPI

Dim X As Integer

Dim Y As Integer

End Structure



Private Function CancelButtonCli cked() As Boolean

Dim p As New POINTAPI

p.X = Form.MousePosit ion.X

p.Y = Form.MousePosit ion.Y

Dim HWnd As IntPtr = WindowFromPoint (p)

If HWnd = CType(Me.Cancel Button, Button).Handle Then

Return True

Else

Return False

End If

End Function

\\\\\\\\\\\\

--
Al Reid

"Al Reid" <areidjr@reidDA SHhome.comwrote in message news:uAhLRUppGH A.2328@TK2MSFTN GP05.phx.gbl...

I had tried all of that, *BUT*, I had neglected to set the button's CausesValidatio n to False. DUH!!!
It does indeed work. I also got the WindowFromPoint approach working as well. Now I can go back and strip that out.
>
Thanks.
>
--
Al Reid (who didn't mean to hijack the thread)
>
>
"Terry" <Terry@nospam.n ospamwrote in message news:70E9A54F-85F3-49D4-AB1E-6EAFC54FCCE9@mi crosoft.com...

Well it works for me - but one thing I left out - you need to set the cancel
buttons 'causes validation' to false. The following code works as you might
hope:
Public Class Form1
Private mCanceling As Boolean = False

Private Sub Button1_Click(B yVal sender As System.Object, ByVal e As
System.EventArg s) Handles Button1.Click
mCanceling = True
Me.Close()
End Sub

Private Sub TextBox1_Valida ting(ByVal sender As Object, ByVal e As
System.Componen tModel.CancelEv entArgs) Handles TextBox1.Valida ting
If Not mCanceling Then
If TextBox1.Text.L ength < 5 Then
e.Cancel = True
End If
End If
End Sub
End Class
The removehandeler method also works.

Also, as I just discovered, if you set the text box's causesvalidatio n to
false, you can close the form from the control box without validation taking
place. This really sounds more like a bug to me.

--


Terry

>
>

[Terry]

Re: Validating textbox w/ Cancel button

Hi Al,
Hmmm, I just tried the 'escape' key and it works fine! The form cancels
and the 'validating' event is skipped. Sounds like you have something else
going on.
--
Terry


"Al Reid" wrote:

Just a follow-up. The thing that this approach does not allow (unless I've one again neglected the obvious) is using the escape key
to trigger the form cancel. If I hit the escape, the validation event fires and since the mCanceling is not True, the validation
error gets displayed before the form closes.
>
My final solution, unless someone has a better suggestion, is to change the Validating event to the Leave event and detecting
whether the cancel button had been clicked in the Leave event and exiting if it was. This way both the escape key and the cancel
button closes the form without causing the validation to occur.
>
The code to tell if the cancel button has been clicked is:
>
///////
>
Public Declare Function WindowFromPoint Lib "user32" (ByVal p As POINTAPI) As IntPtr
>
Public Structure POINTAPI
>
Dim X As Integer
>
Dim Y As Integer
>
End Structure
>
>
>
Private Function CancelButtonCli cked() As Boolean
>
Dim p As New POINTAPI
>
p.X = Form.MousePosit ion.X
>
p.Y = Form.MousePosit ion.Y
>
Dim HWnd As IntPtr = WindowFromPoint (p)
>
If HWnd = CType(Me.Cancel Button, Button).Handle Then
>
Return True
>
Else
>
Return False
>
End If
>
End Function
>
\\\\\\\\\\\\
>
--
Al Reid
>
"Al Reid" <areidjr@reidDA SHhome.comwrote in message news:uAhLRUppGH A.2328@TK2MSFTN GP05.phx.gbl...

I had tried all of that, *BUT*, I had neglected to set the button's CausesValidatio n to False. DUH!!!
It does indeed work. I also got the WindowFromPoint approach working as well. Now I can go back and strip that out.

Thanks.

--
Al Reid (who didn't mean to hijack the thread)


"Terry" <Terry@nospam.n ospamwrote in message news:70E9A54F-85F3-49D4-AB1E-6EAFC54FCCE9@mi crosoft.com...

Well it works for me - but one thing I left out - you need to set the cancel
buttons 'causes validation' to false. The following code works as you might
hope:
Public Class Form1
Private mCanceling As Boolean = False
>
Private Sub Button1_Click(B yVal sender As System.Object, ByVal e As
System.EventArg s) Handles Button1.Click
mCanceling = True
Me.Close()
End Sub
>
Private Sub TextBox1_Valida ting(ByVal sender As Object, ByVal e As
System.Componen tModel.CancelEv entArgs) Handles TextBox1.Valida ting
If Not mCanceling Then
If TextBox1.Text.L ength < 5 Then
e.Cancel = True
End If
End If
End Sub
End Class
The removehandeler method also works.
>
Also, as I just discovered, if you set the text box's causesvalidatio n to
false, you can close the form from the control box without validation taking
place. This really sounds more like a bug to me.
>
--
>
>
Terry
>
>

>
>
>

[Terry]

Re: Validating textbox w/ Cancel button

Are you sure you have set the Cancel button's 'CausesValidati on' to False?
--
Terry


"Darin" wrote:

That doesn't work for me. I am on VB.Net, VS 2003. When I click on the
cancel button it doesn't even get to the cancel.click event until AFTER
it has done the validating.
>
Private Sub Button1_Click(B yVal sender As System.Object, ByVal e As
System.EventArg s) Handles Button1.Click
MessageBox.Show ("Button1_click ")
mCanceling = True
Me.Close()
End Sub
>
Private Sub TextBox1_Valida ting(ByVal sender As Object, ByVal e As
System.Componen tModel.CancelEv entArgs) Handles TextBox1.Valida ting
If Not mCanceling Then
If TextBox1.Text.L ength < 5 Then
e.Cancel = True
End If
End If
End Sub
>
Run the program (make sure the tab stop has the textbox first then the
button), leave the text in textbox to be textbox, click on button, you
will see the message. Run it again, clear out the text in textbox, click
on cancel and you will not see the message - the system is not honoring
the cancel.click because (I guess) the e.cancel=true in _validating.
>
>
Darin
>
*** Sent via Developersdex http://www.developersdex.com ***
>

[Al Reid]

Re: Validating textbox w/ Cancel button

I guess I'm going to have to start with a new project and try it. The
users have "required" several features such as navigation with the enter key
instead of tab and also that all of the text gets selected upon entering a
field, etc. The form's KeyPreview is set to True so that I can handle key
events on the form... Somewhere in all of that, something must be getting
crossed up.

I always get the weird ones. For example, I have another application that
uses a wedge type barcode reader. If I type the info and press enter it
works. If I use a wand type reader, it works. If I connect a gun type, the
program fails and the cursor jumps to a text box that has it's TabStop
property set to False. If I do a debug.Print in the Form's Keypress event
all three methods display the exact same key codes.

Oh well, that's what keeps it interesting.

--
Al Reid

"Terry" <Terry@nospam.n ospamwrote in message
news:EFEE22CF-A2CD-47BC-B07C-17D8D3B10904@mi crosoft.com...

Hi Al,
Hmmm, I just tried the 'escape' key and it works fine! The form cancels
and the 'validating' event is skipped. Sounds like you have something
else
going on.
--
Terry
>
>

[Terry]

Re: Validating textbox w/ Cancel button

Hi again Al,
On the barcode reader problem. Maybe you should be using the KeyDown event
instead of the KeyPress event. They don't receive the same things! here is
a line copied from the documentation: "The KeyPress event is not raised by
noncharacter keys; however, the noncharacter keys do raise the KeyDown and
KeyUp events." My guess is that the gun is sending some noncharacter data to
you. I am new to VB .net comming from VB6, but that was also the case in
VB6. Also in the docs on KeyDown there is a mention of "IsInputKey " which I
will have to look into. If you figure it out first, let me know.

--
Terry


"Al Reid" wrote:

I guess I'm going to have to start with a new project and try it. The
users have "required" several features such as navigation with the enter key
instead of tab and also that all of the text gets selected upon entering a
field, etc. The form's KeyPreview is set to True so that I can handle key
events on the form... Somewhere in all of that, something must be getting
crossed up.
>
I always get the weird ones. For example, I have another application that
uses a wedge type barcode reader. If I type the info and press enter it
works. If I use a wand type reader, it works. If I connect a gun type, the
program fails and the cursor jumps to a text box that has it's TabStop
property set to False. If I do a debug.Print in the Form's Keypress event
all three methods display the exact same key codes.
>
Oh well, that's what keeps it interesting.
>
--
Al Reid
>
"Terry" <Terry@nospam.n ospamwrote in message
news:EFEE22CF-A2CD-47BC-B07C-17D8D3B10904@mi crosoft.com...

Hi Al,
Hmmm, I just tried the 'escape' key and it works fine! The form cancels
and the 'validating' event is skipped. Sounds like you have something
else
going on.
--
Terry

>
>
>

[Al Reid]

Re: Validating textbox w/ Cancel button

Terry,

I guess we have a similar background. 26 years in computing and used VB
since Version 2.

I don't do anything with the barcode data in the KeyPress event. I use it
to catch and handle the "enter" key. I guess I could inspect the data in
the KeyDown event to see if there is a difference. I just don't know what
key code combination could direct focus to a text box control that should
never receive focus since the TabStop property is false and there is no
other code that sets focus to the textbox. The textbox is also ReadOnly.
It's frustrating!!!

--
Al Reid

"Terry" <Terry@nospam.n ospamwrote in message
news:785ACE72-1ED6-4D48-B6A6-EEEECB00E729@mi crosoft.com...

Hi again Al,
On the barcode reader problem. Maybe you should be using the KeyDown
event
instead of the KeyPress event. They don't receive the same things! here
is
a line copied from the documentation: "The KeyPress event is not raised by
noncharacter keys; however, the noncharacter keys do raise the KeyDown and
KeyUp events." My guess is that the gun is sending some noncharacter data
to
you. I am new to VB .net comming from VB6, but that was also the case in
VB6. Also in the docs on KeyDown there is a mention of "IsInputKey " which
I
will have to look into. If you figure it out first, let me know.
>
--
Terry
>
>

>>

[Terry]

Re: Validating textbox w/ Cancel button

Hi Al,
Nearly 40 years for me since my first college FORTRAN IV class! My, how
the years fly!
Well, one of the keys you would not see in either the keypress or keydown
events is the tab key, which of course will move the focus. Why it would
stop on a textbox with tabstop property set to False - I have no idea, unless
it is a behavior of the container its in. As far as the 'gun', it may be
better to write a console app. to read its output.
--
Terry


"Al Reid" wrote:

Terry,
>
I guess we have a similar background. 26 years in computing and used VB
since Version 2.
>
I don't do anything with the barcode data in the KeyPress event. I use it
to catch and handle the "enter" key. I guess I could inspect the data in
the KeyDown event to see if there is a difference. I just don't know what
key code combination could direct focus to a text box control that should
never receive focus since the TabStop property is false and there is no
other code that sets focus to the textbox. The textbox is also ReadOnly.
It's frustrating!!!
>
--
Al Reid
>
"Terry" <Terry@nospam.n ospamwrote in message
news:785ACE72-1ED6-4D48-B6A6-EEEECB00E729@mi crosoft.com...

Hi again Al,
On the barcode reader problem. Maybe you should be using the KeyDown
event
instead of the KeyPress event. They don't receive the same things! here
is
a line copied from the documentation: "The KeyPress event is not raised by
noncharacter keys; however, the noncharacter keys do raise the KeyDown and
KeyUp events." My guess is that the gun is sending some noncharacter data
to
you. I am new to VB .net comming from VB6, but that was also the case in
VB6. Also in the docs on KeyDown there is a mention of "IsInputKey " which
I
will have to look into. If you figure it out first, let me know.

--
Terry

>

>
>
>