c# - Get parameter from url asp.net mvc 4 -

i want parameter url below:

www.domain.com/controller/action/parameter 

in controller:

public actionresult action() {     //some codes } 

user enters url above , should navigate the specific controller. how 'parameter' in action of controller?

example

public actionresult action() {     string param1 = this.request.querystring["param"]; }