A method in an interface can have which of the following? C# code example

Example 1: creating interface in C#

using System;

namespace Grepper_Docs
{
    public interface IWhatever
    {
        bool doSomething(); //Interface methods don't have bodies or modifiers
    }
  
  	class Program : IWhatever
    {
        static void Main(string[] args)
        {
            var pro = new Program();
            pro.doSomething();
        }

        public bool doSomething() //methods must be public
        {
            return true;
        }
    }
}

Example 2: what is inteface and how to use in c#

interface IShape
{
    double X { get; set; }
    double Y { get; set; }
    void Draw();
}

class Square : IShape
{
    private double _mX, _mY;

    public void Draw() { ... }

    public double X 
    { 
        set { _mX = value; }
        get { return _mX; }  
    }

    public double Y 
    {
        set { _mY = value; }
        get { return _mY; }
    }
}