How do i use a loop to count how many lines there are in a richtextbox?

Don't use a loop. You can probably store the text in the richtextbox in a string and split it by newline.

If you look at the members of a RichTextBox, you might notice that it has a "Lines" member.

If you further investigate this "Lines" member, you would notice that it is a string array, which means that you can use the "Length" property.

[code]
length = myRTB.Lines.Length
[/code]

thanks guys! but my dad just helped me do it.
now i can continue on with the easy part.

[quote author=VeBee link=topic=15500.msg156569#msg156569 date=1154829141]
now i can continue on with the easy part.
[/quote]
That *was* the easy part.