using System;

using System.Collections.Generic;

using System.Reflection;

​

public class RequestData

{

    public string PropertName1

    {

        get;

        set;

    }

​

    private string PropertName2

    {

        get;

        set;

    }

​

    public string PropertName3

    {

        get;

        set;

    }

​

    private string PropertName100

    {

        get;

        set;

    }

}

​

public class Program

{

    private static List<Tuple<string, string>> _list;

    public static void Main()

    {

        _list = new List<Tuple<string, string>>{

            new Tuple<string, string>("PropertName1", "asd"), 

            new Tuple<string, string>("PropertName2", "sdfgds"), 

            new Tuple<string, string>("PropertName3", "dfgdfg"), 

            new Tuple<string, string>("PropertName100", "dfgdfg")};

        var requestData = new RequestData();

        foreach (var tuple in _list)

        {

            requestData.GetType().GetProperty(tuple.Item1, BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance)?.SetValue(requestData, tuple.Item2);

        }

​

        Console.WriteLine(requestData.PropertName1);

    }

}