Having issues addressing inheritance in C# -

i'm having trouble understanding how implement inheritance.

my model purely demonstration's sake, here go:

i have parent class bus. has 2 children dieselbus , electricbus. these abstract classes.

i have further 2 classes coach , citybus. how set inherit either dieselbus or electricbus without having define separate coach , citybus classes coachdieselbus, coachelectricbus, citybusdieselbus , citybuselectricbus ? feasible/possible?

i don't have examples short of skeletons far, looking advice on point.

what looking this:

as opposed this:

thanks!

edit (2013-07-03):

first, code:

bus.cs

using system; using system.collections.generic; using system.linq; using system.text;  namespace inheritancetest {     abstract class bus {         public bus () {          }          public abstract engine enginetype {             get;             set;         }          private int id;         public int id {             {                 return id;             }             set {                 id = value;             }         }          private int seats;         public int seats {             {                 return seats;             }             set {                 seats = value;             }         }          private float length;         public float length {             {                 return length;             }             set {                 length = value;             }         }          private string colour;         public string colour {             {                 return colour;             }             set {                 colour = value;             }         }     } } 

coach.cs

using system; using system.collections.generic; using system.linq; using system.text;  namespace inheritancetest {     class coach : bus {         public coach (int id, int seats, float length, string colour, string company, engine engine) {             this.id = id;             this.seats = seats;             this.length = length;             this.colour = colour;             this.enginetype = engine;             this.company = company;         }          public override engine enginetype {             get;             set;         }          private string company;         public string company {             {                 return company;             }             set {                 company = value;             }         }          public override string tostring () {             return (this.id + "\t" + this.seats + "\t" + this.length + "\t" + this.colour + "\t" + this.company + "\t" + this.enginetype.tostring ());         }     } } 

engine.cs

using system; using system.collections.generic; using system.linq; using system.text;  namespace inheritancetest {     abstract class engine {         public engine () {          }          private float power;         public float power {             {                 return power;             }             set {                 power = value;             }         }          private float torque;         public float torque {             {                 return torque;             }             set {                 torque = value;             }         }          private int redline;         public int redline {             {                 return redline;             }             set {                 redline = value;             }         }     } } 

dieselengine.cs

using system; using system.collections.generic; using system.linq; using system.text;  namespace inheritancetest {     class dieselengine : engine {         public dieselengine (float power, float torque, int redline, float displacement, float fueleconomy) {             this.power = power;             this.torque = torque;             this.redline = redline;             this.displacement = displacement;             this.fueleconomy = fueleconomy;         }          private float displacement;         public float displacement {             {                 return displacement;             }             set {                 displacement = value;             }         }          private float fueleconomy;         public float fueleconomy {             {                 return fueleconomy;             }             set {                 fueleconomy = value;             }         }          public override string tostring () {             return "diesel engine";         }     } } 

i'm having problem in program execution:

using system; using system.collections.generic; using system.linq; using system.text;  namespace inheritancetest {     class program {         static void main (string[] args) {             string line;             var diesel = new dieselengine (200f, 550f, 3500, 7.5f, 10f);             var electric = new electricengine (85f, 1000f, 19000, 24f, 65000f);             var city = new citybus (124, 75, 18.5f, "red", "brisbane", electric);             var coach = new coach (777, 120, 22.5f, "blue", "greyhound", diesel);             line = new string ('-', city.tostring ().length * 2);              system.console.writeline ("city buses\n\nid\tseats\tlength\tcolour\tcity\t\tengine type");             system.console.writeline (line);             system.console.writeline (city.tostring ());              system.console.writeline ("\n\ncoach buses\n\nid\tseats\tlength\tcolour\tcompany\t\tengine type");             system.console.writeline (line);             system.console.writeline (coach.tostring ());              system.console.readkey (true);         }     } } 

no matter how try to, cannot access of properties of either of classes inherit engine relevant buses. example, cannot see displacement of dieselengine gave coach "coach."

i have further 2 classes coach , citybus. how set inherit either dieselbus or electricbus without having define separate coach , citybus classes coachdieselbus, coachelectricbus, citybusdieselbus , citybuselectricbus ? feasible/possible?

no, that's not feasible. inheritance relation must fixed, coach must always have same parent classes.

the appropriate solution problem use composition instead of inheritance: coach , citybus both inherit bus. bus has engine property, can set either dieselengine or electricengine.

(sorry crude diagram, had ms paint available right now.)