使用.NET反射可以知道方法是否不是set属性，也不是来自基类

using System;
using System.Reflection;

public class MyClass
{
    public void MyMethod()
    {
        Console.WriteLine("MyMethod");
    }
}

public class MyDerivedClass : MyClass
{
    public new void MyMethod()
    {
        Console.WriteLine("MyDerivedClass.MyMethod");
    }
}

public class Program
{
    public static void Main()
    {
        Type type = typeof(MyDerivedClass);
        MethodInfo methodInfo = type.GetMethod("MyMethod");

        bool isSetPropertyMethod = methodInfo.IsSpecialName && methodInfo.Name.StartsWith("set_");
        bool isFromBaseClass = methodInfo.DeclaringType != type;

        if (!isSetPropertyMethod && !isFromBaseClass)
        {
            Console.WriteLine("The method is neither a set property method nor from the base class.");
        }
        else
        {
            Console.WriteLine("The method is either a set property method or from the base class.");
        }
    }
}