i want javascript to disable the back button of the IE.
thank
This is usually asked to workaround a certain problem which isn't elaborated about at all.
Better elaborate here about the actual problem and ask how to solve it.
Changing the client environment and user experience is a bad practice. Think twice about it.
At any way, the real solutions for the common problems for which this workaround is "invented" are the PRG pattern and disabling of the response caching and in some cases just robustly written code at server side.