set some textbox visible by variable

Hello,everybody~
Now i'm testing my odcl project.
I want to pass one variable （long, for example，1,2,3,4,）to one program, and want to set the first serveral rows of the form in the attachment visible. How could i do this?

For example, if i submit "1"  ,the first row become visible. If i submit "2" , the first and the second row become visible.  is there anyone can provide me with one good idea?  If there are thoundsands of rows, it will be so convinent.

thanks in advance!

You can programmatically change the visibility of elements in a form and resize the form. But a form with thousands of rows with 3 textboxes each makes little sense. Using a Grid is then a better choice.