you should have an object under the hood, shared between form 1 and form 2. The object should hold the lines of texts like an array for all the textboxes. Depending from what you really want in the form2 texbox, you could assign to that textbox the whole array content or write a method in your object under the hood that should be responsible of filling text property of the form2 textbox.
...Unless I too have not understood what you are really trying to get...
...at present time, using mainly Net 4.0, Vs 2010
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