Change Text Value on Runtime

[Radek Budaø]

Hi all,
i have trouble with changing text value of textbox on runtime. I use this
control to display process information about sending e-mail per smtp. I use
external component

Imports devBiz.Net.Mail
which can hadle events by sending mail.
AddHandler client.OnProgre ss, AddressOf Progress
I have function, which can calculate status of process in percent
Public Sub Progress(ByVal sender As Object, ByVal e As ProgressEventAr gs)
Dim percent As Integer = _
CType((CType(e. Position / e.Length * 100, Double)), Integer)
txtMailStatus.T ext = percent
End Sub

Progress Function is called every time, when sending status is changed,
function calculates correctly 'percent' value, but on form i cannot change
default text. Can you anybody help me? Below i attached all source code for
this form.

I have no onLoad Function for this form defined. Is it problem? How can I
changed text value of text box on runtime?

Than you for your help
Radek Budar

Imports System.Text

Imports devBiz.Net.Mail

Public Class frmRegistration Request

Dim frmMailStatusFo rm as New frmMailSendingS tatus

Private Sub sendRequest( ByVal sender As System.Object, ByVal e As
System.EventArg s) _

Handles btnSendRegReq.C lick
Dim strPrijmeni as String

Dim strJmeno as String

Dim strMesto as String

Dim strEmail as String

Dim sql as String

Dim firstRun as Date

Dim regNrUser as Double
Dim mailMsg As MailMessage = New MailMessage

mailMsg.From.EM ail = "aa*@yyy.cz "

mailMsg.To.Add( "XXX","YY*@sezn am.cz")

Dim now as Date

strPrijmeni = txtPrijmeni.Tex t

strJmeno = txtJmeno.Text

strMesto = txtMesto.Text

strEmail = txtEmail.Text

Dim sb As New StringBuilder()

sb.Append(strPr ijmeni)

sb.Append(",")

sb.Append(strJm eno)

sb.Append(",")

sb.Append(strMe sto)

sb.Append(",")

sb.Append(strEm ail)

sb.Append(",")

sb.Append(regNr User)
mailMsg.Subject = "test - " & now

mailMsg.Body = sb.ToString

Dim client As smtp = New smtp

client.Host = "smtp.seznam.cz "

client.Port = 25

' We will capture the progress event, so we attach an event handler

AddHandler client.OnProgre ss, AddressOf Progress
txtMailStatus.V isible = True

'E-mail sending

Try

client.SendMess age(mailMsg)

Catch ex As System.Net.Mail .SmtpException

txtMailStatus.F oreColor = Color.Red

txtMailStatus.T ext = "Failure!"

MsgBox("Odeslán í e-mailu se nezdaøilo, zkontrolujte pøipojení k internetu!"
& vbNewLine & vbNewLine + ex.Message, MsgBoxStyle.Exc lamation, "Chyba pøi
odesílání registraèního e-mailu")

Exit Sub

Finally

End Try
txtMailStatus.F oreColor = Color.Green

txtMailStatus.t ext = "Done...success !"
stavRegistrace = 3

Me.Close

End Sub

Public Sub Progress(ByVal sender As Object, ByVal e As ProgressEventAr gs)

Dim percent As Integer = _

CType((CType(e. Position / e.Length * 100, Double)), Integer)

txtMailStatus.T ext = percent

End Sub

End Class

[Armin Zingler]

"Radek Budaø" <ra*********@as ei.cz> schrieb

Progress Function is called every time, when sending status is
changed, function calculates correctly 'percent' value, but on form
i cannot change default text. Can you anybody help me? Below i
attached all source code for this form.

What do you mean with "default text"? I guess, "txtMailStatus. Text =
percent" is executed but the display isn't updated, right? If this is the
case: There can be two different reasons depending on how the smtp class
works (see it's documentation).

If the OnProgress event is raised in a different thread, you must call
txtMailStatus.I nvoke to marshal updating the textbox to the right thread.
Only the thread that created a control is allowed to access it.

If it's not raised in a different thread, the display isn't updated because
your application is still busy in "client.SendMes sage(mailMsg)" and there's
no time to update the display. In earlier Win versions, you could force
updating the display by calling txtMailStatus.R efresh but this can fail
under WinXP after the application is not "responsive " after few seconds. In
this case you can either create your own thread to send the mail - then you
do have to call txtMailStatus.I nvoke to update the textbox - or, you can use
a simple workaround by calling the PeekMessage API function (faking the
responsiveness of your application) in addition to calling
txtMailStatus.R efresh.

Armin

[Radek Budar]

> What do you mean with "default text"? I guess, "txtMailStatus. Text =

percent" is executed but the display isn't updated, right? If this is the
Yes, correct. Thank you for your advice, i will try it as soon as possible.
Can you say me still one...? How can I find, that onProgress event is raised
in a different thread...? Sorry, I am rookie :-)

Thanks

"Armin Zingler" <az*******@free net.de> píse v diskusním príspevku
news:Ob******** ******@TK2MSFTN GP14.phx.gbl... "Radek Budaø" <ra*********@as ei.cz> schrieb

Progress Function is called every time, when sending status is
changed, function calculates correctly 'percent' value, but on form
i cannot change default text. Can you anybody help me? Below i
attached all source code for this form.

What do you mean with "default text"? I guess, "txtMailStatus. Text =
percent" is executed but the display isn't updated, right? If this is the
case: There can be two different reasons depending on how the smtp class
works (see it's documentation).

If the OnProgress event is raised in a different thread, you must call
txtMailStatus.I nvoke to marshal updating the textbox to the right thread.
Only the thread that created a control is allowed to access it.

If it's not raised in a different thread, the display isn't updated
because
your application is still busy in "client.SendMes sage(mailMsg)" and
there's
no time to update the display. In earlier Win versions, you could force
updating the display by calling txtMailStatus.R efresh but this can fail
under WinXP after the application is not "responsive " after few seconds.
In
this case you can either create your own thread to send the mail - then
you
do have to call txtMailStatus.I nvoke to update the textbox - or, you can
use
a simple workaround by calling the PeekMessage API function (faking the
responsiveness of your application) in addition to calling
txtMailStatus.R efresh.

Armin

[Armin Zingler]

"Radek Budar" <ra*********@as ei.cz> schrieb

What do you mean with "default text"? I guess, "txtMailStatus. Text
= percent" is executed but the display isn't updated, right? If
this is the

Yes, correct. Thank you for your advice, i will try it as soon as
possible. Can you say me still one...? How can I find, that
onProgress event is raised in a different thread...? Sorry, I am
rookie :-)

In the documentation on the class. Or: In Sub Progress, examine the return
value of Me.InvokeRequir ed. If it is True, the event is raised from a
different thread.
Armin

[Radek Budar]

Hallo,
i tried it and...Me.Invoke Required is 'false', also it is not running in
separate thread (i muss say FORTUNATELLY, because use of Invoke method in
now out of my capacity :-). But I made any changes in my Progress procedure,
so text box is now updating...When , after every text box updating, show
message box, text in text box is updated. I dont know why but i know, that
is for me unacceptable. Here is core:

Public Sub Progress(ByVal sender As Object, ByVal e As ProgressEventAr gs)
Dim percent As Integer = _

CType((CType(e. Position / e.Length * 100, Double)), Integer)

txtMailStatus.T ext = percent

MsgBox("Status: " & percent)

End Sub

When I delete 'MsgBox("Status : " & percent)', no update of text box
'txtMailStatus' is displayed!

Any advice now, please...

Best regards

Radek Budar


"Armin Zingler" <az*******@free net.de> píse v diskusním príspevku
news:uZ******** *****@TK2MSFTNG P11.phx.gbl...

"Radek Budar" <ra*********@as ei.cz> schrieb

> What do you mean with "default text"? I guess, "txtMailStatus. Text
> = percent" is executed but the display isn't updated, right? If
> this is the

Yes, correct. Thank you for your advice, i will try it as soon as
possible. Can you say me still one...? How can I find, that
onProgress event is raised in a different thread...? Sorry, I am
rookie :-)

In the documentation on the class. Or: In Sub Progress, examine the return
value of Me.InvokeRequir ed. If it is True, the event is raised from a
different thread.
Armin

[Radek Budar]

Hallo
i tried InvokeRequired and result is 'False'. So, case one, other thread,
is out. I made a little change in my procedure 'progress', after every text
box change, i display message box. Message box displays percent value. After
every display of message box, is text box also updated! I dont know why...?
After delete MessageBox, is no text changed!
Here is my changed procedure. Can you give me advice, what is incorrenc or
why after display message box is text box also updated?

Public Sub Progress(ByVal sender As Object, ByVal e As ProgressEventAr gs)

Dim percent As Integer = _

CType((CType(e. Position / e.Length * 100, Double)), Integer)

txtMailStatus.T ext = percent

MsgBox("Status: " & percent)

End Sub
"Armin Zingler" <az*******@free net.de> píse v diskusním príspevku
news:uZ******** *****@TK2MSFTNG P11.phx.gbl...

"Radek Budar" <ra*********@as ei.cz> schrieb

> What do you mean with "default text"? I guess, "txtMailStatus. Text
> = percent" is executed but the display isn't updated, right? If
> this is the

Yes, correct. Thank you for your advice, i will try it as soon as
possible. Can you say me still one...? How can I find, that
onProgress event is raised in a different thread...? Sorry, I am
rookie :-)

In the documentation on the class. Or: In Sub Progress, examine the return
value of Me.InvokeRequir ed. If it is True, the event is raised from a
different thread.
Armin

[Armin Zingler]

"Radek Budar" <ra*********@as ei.cz> schrieb

Hallo
i tried InvokeRequired and result is 'False'. So, case one, other
thread, is out. I made a little change in my procedure 'progress',
after every text box change, i display message box. Message box
displays percent value. After every display of message box, is text
box also updated! I dont know why...? After delete MessageBox, is no
text changed!
Here is my changed procedure. Can you give me advice, what is
incorrenc or why after display message box is text box also updated?

If you display the messagebox, the application has time to update the
display, including the textbox. To solve this, see my comment "If it's not
raised in a different thread..."

If you're interested in basic information:
http://msdn.microsoft.com/library/en...sagequeues.asp

http://msdn.microsoft.com/library/en...tdraw_1xd1.asp
Armin

[Radek Budar]

Thanks for rich information and for links. I solved the problem follower:

Public Sub Progress(ByVal sender As Object, ByVal e As ProgressEventAr gs)
Dim percent As Integer = _
CType((CType(e. Position / e.Length * 100, Double)), Integer)
txtMailStatus.T ext = percent
Me.Refresh
End Sub

I tested it on WXP, and it looks right :-)

Thank you still one and wish happy new year

Radek Budar
"Armin Zingler" <az*******@free net.de> píse v diskusním príspevku
news:OH******** *****@tk2msftng p13.phx.gbl...

"Radek Budar" <ra*********@as ei.cz> schrieb

Hallo
i tried InvokeRequired and result is 'False'. So, case one, other
thread, is out. I made a little change in my procedure 'progress',
after every text box change, i display message box. Message box
displays percent value. After every display of message box, is text
box also updated! I dont know why...? After delete MessageBox, is no
text changed!
Here is my changed procedure. Can you give me advice, what is
incorrenc or why after display message box is text box also updated?

If you display the messagebox, the application has time to update the
display, including the textbox. To solve this, see my comment "If it's not
raised in a different thread..."

If you're interested in basic information:
http://msdn.microsoft.com/library/en...sagequeues.asp

http://msdn.microsoft.com/library/en...tdraw_1xd1.asp
Armin

[Armin Zingler]

"Radek Budar" <ra*********@as ei.cz> schrieb

Thanks for rich information and for links. I solved the problem
follower:

Public Sub Progress(ByVal sender As Object, ByVal e As
ProgressEventAr gs) Dim percent As Integer = _
CType((CType(e. Position / e.Length * 100, Double)), Integer)
txtMailStatus.T ext = percent
Me.Refresh
End Sub

I tested it on WXP, and it looks right :-)

Good to hear, but if you cover and uncover your Form, or click onto it once,
the progress might be gone. This might take some seconds til the OS
considers your application to be hung (although it isn't).
Thank you still one and wish happy new year

Wish you the same.

Armin