Grabbing Control from Listview

 Hello.
 I have a listview, a textbox, a button and a label below the button, all in the listview.
I want that when I click the button, the label.Text to get the textbox's value. But I cannot read the ID's of these controls in my code behind page. I tried something like this.
1 Label label = (Label)Listview.FindControls("LabelID");
2 label.Text = ...
  But I only can get the label values through this way, I cannot set them to appear in my listview. I made an protected Listview ItemDataBound event method, and there its working to set values to the controls, but it's impossible to put my protected Button_Onclick method inside that one.
Do you have a solution?
Thank you in advance.

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