c# - If and Switch statements; Is there an easier way of producing this code? -

my code follows:

namespace calculation {     class program     {     static void main(string[] args)     {         console.writeline("this system calculate speed, distance or time.");         console.writeline("1 = speed - 2 = distance - 3 = time");         console.writeline("please enter calculation perform. 1, 2 or 3");          string usercalculation = console.readline();         int calculation = int.parse(usercalculation);          if(calculation < 1)         {             console.writeline("please enter number greater or equal 1 less 3.");         }          if (calculation > 3)         {             console.writeline("please enter number less 3 greater or equal 1.");         }          else         {             switch (calculation)             {                 //this statement calculates speed.                 case 1:                     console.writeline("you have chose calculate speed. s = d/t");                      console.writeline("to work out need firstly enter distance in metres");                     string userdistance = console.readline();                     int distance = int.parse(userdistance);                      console.writeline("now enter time in seconds.");                     string usertime = console.readline();                     int time = int.parse(usertime);                      console.writeline("your speed " + distance / time + " m/s");                     console.writeline("in mph " + distance / time * 2.23 + "mph");                     break;                  //this statement calculates distance.                 case 2:                     console.writeline("you have chose calculate distance. d = sxt");                      console.writeline("to work out need firstly enter speed");                     string userspeed = console.readline();                     int speed = int.parse(userspeed);                      console.writeline("now enter time in hours.");                     string usertime1 = console.readline();                     double time1 = double.parse(usertime1);                      console.writeline("your distance " + speed * time1 + " miles");                     break;                  //this statement calculates time.                 case 3:                     console.writeline("you have chose calculate time. t = d/s");                      console.writeline("to work out need firstly enter distance in miles.");                     string usermiles = console.readline();                     int miles = int.parse(usermiles);                      console.writeline("now enter speed in mph.");                     string userspeed2 = console.readline();                     double speed2 = double.parse(userspeed2);                      console.writeline("your time " + miles / speed2 + "hours.");                     console.writeline("this " + miles / speed2 * 60 + " minutes");                     break;             }         }      } } } 

you can remove 1 if statement not diffrent die other if statement. replace one:

        if (calculation < 1 || calculation > 3)         {             console.writeline("please enter number greater or equal 1 less 3.");         } 

create 2 funtions return user input 1 int , second double return type.

    private int getintuserinput()     {         string userinput = console.readline();         int converteduserinput = int.parse(userinput);          return converteduserinput;     }      private double getdoubleuserinput()     {         string userinput = console.readline();         double converteduserinput = double.parse(userinput);          return converteduserinput;     } 

and should move calculations funtion can use enum better readability.

    enum options     {         speed,         time,         distance     }        //example       options calculation = (options)calculation; //cast user input number                                                    // option enum        switch (calculation)       {        case options.distance:            // code        break;        case options.speed:            // code        break;       }