Using items from a listview in C#

I created a listview where I can add items ... When I enter an item and I press "tab" to go to another control, then I have a problem ! I want to do something with the value I entered in the event "Leave" for that listview, but when I check the value, it''''s always empty ... allthough I entered a value ... Is there anyone who has an idea why this occurs and how i can solve this problem ? Thanks !

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