expression.cs

using System;
using System.Linq.Expressions;
using System.Reflection;

namespace Playground
{
    public class Attr : Attribute
    {
        private int v;

        public Attr(int v)
        {
            this.v = v;
        }
    }

    public class Base
    {
        [Attr(1)]
        public virtual string Bar { get; set; }
    }

    public class Child : Base
    {
        [Attr(1)]
        public override string Bar { get; set; }
    }

    public static class PropertyHelper<T>
    {
        public static PropertyInfo GetProperty<TValue>(
            Expression<Func<T, TValue>> selector)
        {
            Expression body = selector;
            if (body is LambdaExpression)
            {
                body = ((LambdaExpression)body).Body;
            }
            switch (body.NodeType)
            {
                case ExpressionType.MemberAccess:
                    return (PropertyInfo)((MemberExpression)body).Member;
                default:
                    throw new InvalidOperationException();
            }
        }
    }

    class Program
    {
        public static void Main()
        {
            PropertyInfo prop = PropertyHelper<Child>.GetProperty(x => x.Bar);

        }
    }
}