c#如何将静态类分配给实例变量？

Question

Static members can't be called with instance, like instance.myStaticProperty .

Is there any way, that I can have an instance variable that will be an alias of static self class? like:

class myClass
{
    public string a ="hello";
    public static string b ="world";

    public myClass myVariable = global::myClass;   // <--- phseudo code
}

and i could call:

myClass instance= new myClass();
instance.myVariable.b; //

Answer 1

No, there is not. The closest you get is using a using .

Your static class definition:

class ClassA
{
    public static string A = "A";
}

And to use it:

using StaticClassA = ConsoleApp1.ClassA;

class Program
{
    static void Main(string[] args)
    {
        string a = StaticClassA.A;
    }
}

Not too much to gain though, but it might ease your naming a little.

Another (somewhat cooler) option is a static using :

using static ConsoleApp1.StaticClassA;

class Program
{
    static void Main(string[] args)
    {
        string a = A;
    }
}

Answer 2

You're attempting to do an anti-pattern there.

Static properties are properties not defined in an instance (object) of that class, but by the class itself. And as such, you can access and modify them whenever you choose to, provided you have the required scopes to do so.

I don't see the problem in calling MyClass.StaticProperty = <some expression> , if indeed the functions the static property do, are static. If it's something part of the object, something you don't connect with the class itself, ie it might be different for each instanced object of that class, then just turn it into a regular property instead.

Example of some static properties and methods:

public class DoMath
{
   public static string Pi { get; private set; } = "3.14";
   public static double X {get; set;}
   public static double Y {get; set;}

   public static double Sum() => X + Y;
}

DoMath.X = 3.5;
DoMath.Y = 4;
double result = DoMath.Sum();
Console.WriteLine($"Pi is equal to {DoMath.Pi}.");

If you truly wish something to be static, then don't try to make it non-static. Simply declare it as such.

Answer 3

Static members are shared across all instances of the class or all instances of Class Of T of same T.

So you can access static properties outside of class by using the ClassName.VarName or directly by the VarName from within the class.

You can access static fields and properties and methods from all non static methods.

You can also add an instance member mapping a static member.

Instances of a static thing can't exist in addition to the static existence itself.

So you can write this:

class myClass
{
  public string a = "hello";

  static public string b = "world";

  public string B { get { return b; } set { b = value; } }

  public void DoSomething()
  {
    b = "new world";
  }
}

And use it like that:

myClass instance= new myClass();
instance.DoSomething();
myClass.b = "another world";
instance.B = "C# world";