Replace javascript on a site with Greasemonkey

does anyone know how t开发者_C百科o replace JavaScript on a site with Greasemonkey ie.

This is the default code:

var Test="1";

And i want to replace it like this on the page load:

var Test="2";

Thanks in advance!

Try the following in a userscript, assuming Test is a global variable:

unsafeWindow.Test="2";