Access private fields

Question

Is it possible to get or set private fields?

I want to get System.Guid.c. Is there a way to access it or should I just copy the code from the strut and make the fields public?

Answer 1

You can use reflection as suggested by Quantic Programming

var guid = Guid.NewGuid();
var field= typeof (Guid).GetField("_c", BindingFlags.NonPublic |BindingFlags.GetField | BindingFlags.Instance);
var value = field.GetValue(guid);

Although if you are okay with first converting the guid to a byte array, I might suggest:

var guid = Guid.NewGuid();
var c = BitConverter.ToInt16(guid.ToByteArray(), 6);

The latter approach avoids using reflection.

Edit

You mention needing to be able to set the value as well, you can still avoid reflection:

var guid = Guid.NewGuid();
var guidBytes = guid.ToByteArray();

// get value
var c = BitConverter.ToInt16(guidBytes, 6);

// set value
Buffer.BlockCopy(BitConverter.GetBytes(c), 0, guidBytes, 6, sizeof(Int16));
var modifiedGuid = new Guid(guidBytes);

Answer 2

You should try System.Reflection. Here's an example:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Reflection;

namespace AccessPrivateField
{
    class foo
    {
        public foo(string str)
        {
            this.str = str;
        }
        private string str;
        public string Get()
        {
            return this.str;
        }
    }
    class Program
    {
        static void Main(string[] args)
        {
            foo bar = new foo("hello");
            Console.WriteLine(bar.Get());
            typeof(foo).GetField("str", BindingFlags.NonPublic | BindingFlags.Instance).SetValue(bar, "changed");
            Console.WriteLine(bar.Get());
            //output:
            //hello
            //changed
        }
    }
}