Web Custom Control: getting a updated value on Load event after a postback

[ronchese]

Hello.

I wrote a Web Custom Control that have a property named SelectedValue. This SelectedValue property is set after the user clicks a LinkButton control, by its Click() event.

I did some tests, and I noticed that my handled LinkButton_Clic k() event is fired only after the Page_Load() event, due to page and control lifecicles.

The result of this is, when in Page_Load(), I can only catch the SelectedValue from a previous postback (out of sync).

BUT.... I know and yet did a test with a RadioButtonList . I can retrieve the updated SelectedValue in the Page_Load event with no problem!!

Anyone know the trick so I can update my SelectedValue before the Page_Load() event, soon after the user clicks a LinkButton?

Example (just relevant pieces - better viewed in RichText format):

WebCustomContro l:
'retrieves from/sets to viewstate. This property is started with zero ("0")
<DefaultValue(F alse), Browsable(False )_
Public Property SelectedValue() As Integer
Get
Return CInt(ViewStateC lass.Retrieve(V iewState, "SelectedValue" , "0"))
End Get
Set(ByVal value As Integer)
ViewStateClass. Save(ViewState, "SelectedValue" , CInt(value))
End Set
End Property

'this is where I set the SelectedValue (this event was previously attached via AddHandler)
Private Sub LinkButtonClick (ByVal sender As Object, ByVal e As System.EventArg s)
Me.SelectedValu e = lnk.CommandArgu ment
End Sub

Page:
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArg s) Handles Me.Load
Label1.Text = MyControl.Selec tedValue '<= on first postback, it returns "0", even
'if the user clicks a LinkButton that returns 20. On second postback, that 20 will
'be returned. Or shortly, it is out of sync.
End Sub

[Mr. Arnold]

"ronchese" <info(a)carsoft net.com.brwrote in message
news:%2******** ********@TK2MSF TNGP04.phx.gbl. ..
Hello.

I wrote a Web Custom Control that have a property named SelectedValue. This
SelectedValue property is set after the user clicks a LinkButton control, by
its Click() event.

I did some tests, and I noticed that my handled LinkButton_Clic k() event is
fired only after the Page_Load() event, due to page and control lifecicles.

The result of this is, when in Page_Load(), I can only catch the
SelectedValue from a previous postback (out of sync).

BUT.... I know and yet did a test with a RadioButtonList . I can retrieve the
updated SelectedValue in the Page_Load event with no problem!!

Anyone know the trick so I can update my SelectedValue before the
Page_Load() event, soon after the user clicks a LinkButton?

http://www.15seconds.com/issue/020102.htm

I don't know. Maybe using a Session variable and understanding the ASP.NET
Page Life Cycle and where you can possibly intercept things.

[ronchese]

As I understood, even a session variable can itself solve this problem.
It is because the LinkButton_Clic k() event is raised *after* the Page_Load()
event.

I guess there is a switch or a trick to resolve this.

As MSDN says, Control Events are raised after Page Load:
http://msdn2.microsoft.com/en-us/library/ms178472.aspx
I'm thirsty to find the trick :P


"Mr. Arnold" <MR. Ar****@Arnold.c omwrote in message
news:eE******** ******@TK2MSFTN GP03.phx.gbl...

>
"ronchese" <info(a)carsoft net.com.brwrote in message
news:%2******** ********@TK2MSF TNGP04.phx.gbl. ..
Hello.

I wrote a Web Custom Control that have a property named SelectedValue.
This SelectedValue property is set after the user clicks a LinkButton
control, by its Click() event.

I did some tests, and I noticed that my handled LinkButton_Clic k() event
is fired only after the Page_Load() event, due to page and control
lifecicles.

The result of this is, when in Page_Load(), I can only catch the
SelectedValue from a previous postback (out of sync).

BUT.... I know and yet did a test with a RadioButtonList . I can retrieve
the updated SelectedValue in the Page_Load event with no problem!!

Anyone know the trick so I can update my SelectedValue before the
Page_Load() event, soon after the user clicks a LinkButton?

http://www.15seconds.com/issue/020102.htm

I don't know. Maybe using a Session variable and understanding the ASP.NET
Page Life Cycle and where you can possibly intercept things.

[ronchese]

Guess I found the trick. It is a workaround, but it works.

http://devsushi.com/2006/09/01/aspne...ntrols-part-2/

[]s
Cesar


"ronchese" <info(a)carsoft net.com.brwrote in message
news:Ol******** ******@TK2MSFTN GP05.phx.gbl...

As I understood, even a session variable can itself solve this problem.
It is because the LinkButton_Clic k() event is raised *after* the
Page_Load() event.

I guess there is a switch or a trick to resolve this.

As MSDN says, Control Events are raised after Page Load:
http://msdn2.microsoft.com/en-us/library/ms178472.aspx
I'm thirsty to find the trick :P


"Mr. Arnold" <MR. Ar****@Arnold.c omwrote in message
news:eE******** ******@TK2MSFTN GP03.phx.gbl...

>>
"ronchese" <info(a)carsoft net.com.brwrote in message
news:%2******* *********@TK2MS FTNGP04.phx.gbl ...
Hello.

I wrote a Web Custom Control that have a property named SelectedValue.
This SelectedValue property is set after the user clicks a LinkButton
control, by its Click() event.

I did some tests, and I noticed that my handled LinkButton_Clic k() event
is fired only after the Page_Load() event, due to page and control
lifecicles.

The result of this is, when in Page_Load(), I can only catch the
SelectedValu e from a previous postback (out of sync).

BUT.... I know and yet did a test with a RadioButtonList . I can retrieve
the updated SelectedValue in the Page_Load event with no problem!!

Anyone know the trick so I can update my SelectedValue before the
Page_Load() event, soon after the user clicks a LinkButton?

http://www.15seconds.com/issue/020102.htm

I don't know. Maybe using a Session variable and understanding the
ASP.NET Page Life Cycle and where you can possibly intercept things.