Accessing VB .Net Controls from Javascript

[fripper]

Suppose I have a textbox that was created in a VB .Net web application in
design mode ... the name of the textbox is txtCount and its text property is
initially set to 10. Now I go into HTML view and want to add some
JavaScript code to initiate a countdown timer that every second decrements
the value in txtCount.text. I know how to handle the timer itself but I do
not know specifically how to access the txtCount textbox so that I can
change its text property to 9 ... then 8 ... etc.

I am beginning to get a handle on VB .Net and JavaScript but I am at a loss
to see how I can reference a .Net object in JavaScript ... and while there
is a wealth of technical help on these systems I don't see any examples of
the sort of thing described in the preceding paragraph

[Cor]

Re: Accessing VB .Net Controls from Javascript

Hi Fripper,

A while ago I made this sample. It is really a sample, you should not use it
in a real environment, however it shows some things I think that you are
asking.

I hope this helps?

Cor

\\\Form 1 Needs a imagebox on the page
Private Sub Page_Load(ByVal sender As System.Object, _
ByVal e As System.EventArg s) Handles MyBase.Load
Me.Image1.Heigh t = New Unit(32)
Me.Image1.Width = New Unit(200)
Image1.Visible = True
Dim scriptString As String = "<script language=JavaSc ript>" & _
"setclock() ; function setclock(){docu ment.images.Ima ge1.src = " & _

"'http://localhost/WebClock/WebForm2.aspx'; setTimeout('set clock()',1000)} </s
cript>"
Page.RegisterSt artupScript("se tclock", scriptString)
End Sub
///
\\\Form2 needs nothing
Private Sub Page_Load(ByVal sender As System.Object, _
ByVal e As System.EventArg s) Handles MyBase.Load
Response.Cache. SetExpires(Date Time.Now.AddTic ks(500))
Dim myForeBrush As Brush = Brushes.Black
Dim myFont As New Font("Times New Roman", 8, FontStyle.Regul ar)
Dim textHeight As Single
Dim bm As New Bitmap(120, 20)
Dim g As Graphics = Graphics.FromIm age(bm)
g.Clear(Color.W hite)
Dim textSize As SizeF = g.MeasureString ("now.tostring" , myFont)
g.DrawString(No w.ToString, myFont, myForeBrush, _
New RectangleF(0, 0, 120, 20))
Dim ms As New IO.MemoryStream
Dim arrImage() As Byte
bm.Save(ms, Imaging.ImageFo rmat.Bmp)
arrImage = ms.GetBuffer
Response.Binary Write(arrImage)
End Sub
///

[Cor]

Re: Accessing VB .Net Controls from Javascript

Fripper,

However, this is I think a direct the answer on your question.

I hope this helps?

Cor

\\\Needs a download of LiveClock which has to be placed in the application
folder
\\\\and a webform table with 1 row and 1 cell on the form named Table1

http://www.zip.com.au/~astroboy/liveclock/

Private Sub Page_Load(ByVal sender As Object, ByVal e _
As System.EventArg s) Handles MyBase.Load
Dim str As String = "<script language=javasc ript " & _
"src='liveclock .js'>show_clock ()</script>"
Page.RegisterCl ientScriptBlock ("LiveClock" , str)
Me.Table1.Rows( 0).Cells(0).Tex t = _
"<script language='javas cript'>new LiveClock();</script>"
End Sub
///