vb.net - VB Clear text file before writing -

on click of button want write textbox.text text file. got code working, want clear textfile before writing , not add text.

    dim file system.io.streamwriter     file = my.computer.filesystem. _     opentextfilewriter(mfilename, true)     file.writeline(textbox1.text)     file.close() 

any appreciated.

simply

my.computer.filesystem.opentextfilewriter(mfilename, false) 

where false disables appending , activates overwriting.