multiple visa going to canada & return the same way through china.

Dear messers: I, an Iranian have a multiple long term visa of Canada and would like to go there (Canada west) through china (Beijing & Shanghai) and return the same way while my Canadian visa is valid more than 4.5 years Remain validation.
Can i get Chinese multiple long term entry permit the same, for multi traveling harmonizations?
thanks and remain,
Bozorgzadegan A.