Aceessing controls in a Panel

I dynamically create some controls at runtime and add them into a panel.

Later on, I try to access those controls in a different function, butI get a null object error

Does anybody know what Im doing wrong?
Protected Sub TreeView1_SelectedNodeChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles TreeView1.SelectedNodeChanged
 
   Dim TextBox1 As New TextBox
   TextBox1.ID = "a"
   TextBox1.Style("Position") = "Absolute"
   Panel1.Controls.Add(TextBox1)
 
end sub
 
Protected Sub btnSubmit_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnSubmit.Click
 
        Dim txt As TextBox = New TextBox()
 
        txt = Panel1.FindControl("a")   'crash here
        Label1.Text = txt.Text
 
end sub

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bdb12Asked:
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dinomixCommented:
Instead of setting textbox.id set textbox.name = "a".
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dinomixCommented:
Also, try accessing panel1 by preceeding with me. So me.panel1.findcontrol("a").

My previous post is incorrect by the way, i confused with another method.
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bdb12Author Commented:
ok I cant find an attribute of Name for textboxs....

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appariCommented:
the problem is dynamic controls are lost on postback, if you dont create them again in page load event. try the same code from btnsubmit_click event in page load event, it will work. you need to add a check to check if it is  a postback case.

check this for a sample
http://forums.asp.net/t/1186195.aspx
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bdb12Author Commented:
Ah I didnt know they where lost....that makes sense....I'll try out that code now and get back to you. Thx
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bdb12Author Commented:
Still working on this....home time now so will get into it tomorrow....thx
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Éric MoreauSenior .Net ConsultantCommented:
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bdb12Author Commented:
Thank you
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