How do I get the API after setting a text box to goto the last word in the text box?

[gthkane]

I'm having a problem with figuring this out so, how would I goto the last word in a textbox after setting the text box text? For example I put the text "lala" into a textbox and it'll put the cursor to the beginning of the text how would I get the cursor to goto the end instead of the beginning?