need something like clear fields using a button

Hello

Im trying to do something like to put a button to clear some fileds. becouse i want to clear fields type file name to cancel if the user mistake selecting the file. sc havent a cancel button after to selected file. so i dont know how to do that. Any body have some solution or idea?

Thanks and sorry for my english.

I think you can do it with a button type javascript.
i the script you set:
document.F1.myfield.value = ‘’;

hi thanks for answer
can i ask what is the name of form that i need to use? always its F1? or is it somethink like my application name?

Allways is F1.