using System;

using System.Linq.Expressions;

​

public class Program

{

    public static void Main(string[] args)

    {

        Target target = new Target();

​

        Source source = new Source()

        {

            NestedField = new NestedSource()

            {

                Dummy = "Hello world"

            }

        };

​

        var action = Map<Source, Target>(p => p.NestedField.Dummy, x => x.TargetName);

        action(source, target);

​

        Console.WriteLine(target.TargetName);

    }

​

    public static Action<TSource, TTarget> Map<TSource, TTarget>(Expression<Func<TSource, object>> getter, Expression<Func<TTarget, object>> setter)

    {

        var sourceField = getter.Body as MemberExpression;

        var targetField = setter.Body as MemberExpression;

        // here we create new assign expression

        var assign = Expression.Assign(targetField, sourceField);

​

        // and then compile it with original two parameters

        var lambda = Expression.Lambda<Action<TSource, TTarget>>(assign, getter.Parameters[0], setter.Parameters[0]);

        return lambda.Compile();

    }

}

​

public class Target

{

    public string TargetName { get; set; }

}

​

public class NestedSource

{

    public string Dummy { get; set; }

}

​

public class Source

{

    public NestedSource NestedField { get; set; }

}

​