using System;

using System.Reflection;

using System.Collections.Generic;

using System.Linq.Expressions;

public class Program

{

    public static void Main()

    {

        FindPropertyNames<Student>(x => new object[] { x.Name, x.Age, x.Country }).Dump();

        FindPropertyNames<Student>(x => x.Name + x.Age + x.Country).Dump();

    }

    public static List<string> FindPropertyNames<T>(Expression<Func<T, object>> expr)

    {

        var visitor = new FindPropertiesVisitor(expr.Parameters[0]);

        visitor.Visit(expr);

        return visitor.Names;

    }

}

​

public class FindPropertiesVisitor : ExpressionVisitor

{

    private readonly Expression parameter;

    public List<string> Names { get; } = new List<string>();

​

    public FindPropertiesVisitor(Expression parameter) => this.parameter = parameter;

​

    protected override Expression VisitMember(MemberExpression node)

    {

        if (node.Expression == parameter)

        {

            Names.Add(node.Member.GetCustomAttribute<JsonPropertyAttribute>().PropertyName);

        }

        return node;

    }

}

​

public class Student

{

    [JsonProperty("name")]

    public string Name { get; set; }

​

    [JsonProperty("age")]

    public int Age { get; set; }

​

    [JsonProperty("country")]

    public string Country { get; set; }

}

​

public class JsonPropertyAttribute : Attribute

{

    public string PropertyName { get; set; }

    public JsonPropertyAttribute(string name) => PropertyName = name;

}