Question

I have in here an old web application written in ASP.Net 2.0 + AJAX.

I have in my page a textbox control and a button and a label control which is inside an update panel.

A text will be entered into the textbox and subsequently, on the textchanged event of the control, some server side processing and data validations are involved.

I am using the label control as a display to inform the user of the progress of the validation. Different messages may appear at the label control.

In the current scenario, only the last string specified for the label control is displayed on the label control.

I am looking for ways on how to be able to display different text on the label control, say at interval of 5 seconds.

Is there an AJAX Control there for this (or something similar which I could use), where I could specify the text to be displayed at n interval of seconds?

How do I achieve this? Inputs highly appreciated. Thanks.

Edited
I think I may need to re-phrase this question to make it simpler.

After an asp.net page post back, how would I be able to specify different text string in a label control which should display after every n seconds?

Like

Label1.Text = “Message 1”

.. Delay 5 seconds

Label1.Text = “Next Message”

.. Delay 5 seconds

Label1.Text = “Another Message”

.. Delay 5 seconds

Label1.Text = “Last Message”

In the current post back model (which includes AJAX UpdatePanel), only the last message is displayed.

Kindly advise. Thanks.

Answer 1

If the label control is contained in the update panel, then call your code using a System.Timers.Timer

Dim WithEvents timer As New System.Timers.Timer()
Dim msgStack As Stack(Of String) = Nothing

Sub DisplayMsg(ByVal msg() As String, ByVal interval As Integer)
    msgStack = New Stack(Of String)
    For i As Integer = 0 To msg.Length - 1
        msgStack.Push(msg(i))
    Next

    timer.Interval = interval
    timer.AutoReset = True
    timer.Start()
End Sub

Private Sub timer_Elapsed(ByVal sender As Object, ByVal e As System.Timers.ElapsedEventArgs) Handles timer.Elapsed
    If msgStack.Count > 0 Then
        Label1.Text = msgStack.Pop()
    Else
        timer.Stop()
    End If
End Sub

Order your message input list last status message to first status message

Sub DoOperation()
    DisplayMsg(New String() {"LastMessage", "Second Message", "First Message"}, 5000)
End Sub