how to write the methods inside the enum in c#

Question

I have a enum and i am calling the methods inside the enum. THis is working fine in java , but i am anot able to covert it in c#

 public enum RomanConverter {

            a("a",1),
            b("b",5),
            c("c",10),

            private String name;
            private int value;

            public String getName() {
                return name;
            }
//here i am setting the value        
            public void setName(String name) {
                this.name = name;
            }

            public int getValue() {
                return value;
            }

            public void setValue(int value) {
                this.value = value;
            }
            RomanConverter(String name, int value){
                this.name = name;
                this.value = value;
            }
  // here is am getting the value  
            public static int getValueByRoman(String roman){
                switch(roman){
                    case "a":
                        return RomanConverter.a.getValue();
                    case "b":
                        return RomanConverter.b.getValue();
                    case "c":
                        return RomanConverter.c.getValue();

                    default:
                        return 0;
                }
            }


        }

I want to convert this code in the c#.I am using the [Descprtion] attribute to set the key and then assigning the value to the value. But it is giving me error "Expected class, delegate, enum, interface, or struct"