How to execute 7zip commands from nant script?

I need to execute 7zip commands from nant script. How can I do that?

I have tried it like this, but it is开发者_开发知识库 not working

&ltexec program="7z.exe" basedir="${sevenzipinstalldir}" commandline="7z a D:\NantTest\Experiment\NewLab\7ziptest.zip -pmypassword D:\NantTest\Experiment\NewLab\"

<exec program="7z.exe" basedir="${sevenzipinstalldir}" commandline="a D:\NantTest\Experiment\NewLab\7ziptest.zip -pmypassword D:\NantTest\Experiment\NewLab\" />

(Don't repeat the executable name in commandline.)