C#：从另一个类访问枚举

Question

I know I can put my enum at the Namespace area of a class so everyone can access it being in the same namespace.

// defined in class2
public enum Mode { Selected, New, }  

What I want is to access this enum from

public class1
{
   var class2 = new class2();
   // Set the Mode
   class2.Mode = Model.Selected
}

Is this somehow possible without using namespace area?

Answer 1

You can declare an enum outside of a class:

namespace MyNamespace
{
    public enum MyEnum
    {
        Entry1,
        Entry2,
    }
}

And then you can add using MyNamespace; where it needs to be used.

Answer 2

Aaron's answer is very nice but I believe there is a much better way to do this:

public static class class1
{
    public void Run()
    {
        class2.Mode mode = class2.Mode.Selected;

        if (mode == class2.Mode.Selected)
        {
            // Do something crazy here...
        }
    }
}

public static class class2
{
    public enum Mode
    { 
        Selected, 
        New
    } 
}

No point over complicating this. It is a simple task.

All the Best

Chris.

Answer 3

Yes:

class2.Mode = class2.Mode.Selected

But note that you can't have a nested type defined that has the same name as one of the outer class' members, so this code will not compile. Either the enum or the property will need to be named something else. Your class name and variable name conflict too, making this a bit more complex.

To make this a more generic answer, if you have this:

public class Foo
{
    public SomeEnum SomeProperty { get; set; }

    public enum SomeEnum {
        Hello, World
    }
}

Then this code will assign an enum value to the property:

Foo foo = new Foo();
foo.SomeProperty = Foo.SomeEnum.Hello;

Answer 4

If you are trying to do what is described below it will not work...

    public class MyClass1
    {
        private enum Mode { New, Selected };
        public Mode ModeProperty { get; set; }
    }

    public class MyClass2
    {
        public MyClass2()
        {
            var myClass1 = new MyClass1();

            //this will not work due to protection level
            myClass1.ModeProperty = MyClass1.Mode.
        }
    }

What you could do however is below, which will work...

    public interface IEnums
    {
        public enum Mode { New, Selected };
    }

    public class MyClass1
    {
        public IEnums.Mode ModeProperty { get; set; }
    }

    public class MyClass2
    {
        public MyClass2()
        {
            var myClass1 = new MyClass1();

            //this will work
            myClass1.ModeProperty = IEnums.Mode.New;
        }
    }

Answer 5

I ended up solving my issue by changing it to a namespace accessor, found by utilizing Intellisense. I thought the enum was in the class, not just the namespace. If it was in the class, I would recommend moving it out of the class.

namespace ABC.XYZ.Contracts
{
  public class ChangeOrder : BaseEntity, IAuditable
  {
     ...
  }

  public enum ContractorSignatureType
  {
    A,
    B,
    V
  }
}

ContractorSignatureType = Contracts.ContractorSignatureType.B,

Answer 6

    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Text;
    using System.Threading.Tasks;

    namespace @enum
    {
        class temp
        {
           public enum names
            {
                mohitt,
                keval,
               Harshal,
               nikk
            }

        }


        class Program
        {

            static void Main(string[] args)
            {

                Console.WriteLine((int)temp.names.nikk);
                Console.ReadKey();

            }
        }
    }

Answer 7

//by using this you can access the value of enum.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace @enum
{
    class temp
    {
       public enum names
        {
            mohitt,
            keval,
           Harshal,
           nikk
        }

    }
    class Program
    {

        static void Main(string[] args)
        {

            Console.WriteLine(temp.names.nikk);
            Console.ReadKey();

        }
    }
}