Simulation has become a significant way for performance evaluations in switching and scheduling, however, the existing simulation softwares have some limitations in inheritability and extensibility. Based on the current crossbar switching fabric, by employing system level design method, and object oriented technology, a simulation platform called SPES (switching performance evaluation system) for switching fabrics and scheduling policies' developments are designed and implemented. Input queuing, output queuing, combined input-output queuing and combined input-crosspoint queuing and corresponding scheduling policies are integrated. Inheritability and extensibility attributes are obtained by designing traffic sources, switching fabrics and scheduling policies separately, and it exhibits good performances for supporting multi-fabric, variable packets sizes and QoS model's simulations. By configuring the platform through a uniform view, users can fulfill their concrete simulation environment. Besides, it can carry out end to end performances' evaluations with little modification. Finally, this paper presents a simulation case based on combined input-crosspoint queuing switch, displaying the good performance of SPES.