Commented Unassigned: cd command not working in Renci.SshNet.SshClient [2012]

I am using the dll of Renci.SshNet in my project for connecting to Linux server.
i have test and found that I am not able to run cd command by Renci.SshNet.SshClient object.

when i run the command it doesnot produce error.
so, i run pwd command to check path and found that it is still in same directory.

Help me.
i need to run cd command..

sampe code attached...
Comments: ** Comment from web user: da_rinkes **

What does the command "pwd && cd .. && pwd" give you?

RunCommand uses SSH exec, which runs all commands in a new context.
If you have a series of commands which depend on each other, combine them (with '&&', '||', ';') or
use a shell stream (which keeps the context).

RunCommand does the same like:

ssh -l user host command
or
plink.exe -l user host command