Reloading movieclip as variables change

Okay, i am working on a flash website and i have for the first time made everything dynamically loading from outside of the SWF to reduce the file size. I have a text file which is dynamically loaded into a text box, which i have defined in a variable called “textfile”. I want to reload the movieclip on the click of a button and at the same time change the variable for the text file to be opened into the text box. so as i click content, the variable changes to content and the movieclip reloads, showing content.txt in the text box, does anyone have any idea of how i would go about this?

thanks for your help.