Run dynamically compiled C# code at native speed… how?

Question

I have read several posts on SO about writing and compiling dynamic C# code. For example, this post. I understand it can be done several ways.

However, calling the c

Answer 1

Thought it was worth showing how all potential options looked and their performance characteristics. Given the following helper classes and functions:

public void Test(Func func)
{        
    var watch = new Stopwatch();
    watch.Start();
    for (var i = 0; i <= 1000000; i++)
    {
        var test = func();
    }
    Console.WriteLine(watch.ElapsedMilliseconds);
}

public class FooClass { public int Execute() { return 1;}}

Set up and execution:

using (Microsoft.CSharp.CSharpCodeProvider foo = 
       new Microsoft.CSharp.CSharpCodeProvider())
{
    var res = foo.CompileAssemblyFromSource(
        new System.CodeDom.Compiler.CompilerParameters() 
        {  
            GenerateInMemory = true 
        }, 
        "public class FooClass { public int Execute() { return 1;}}"
    );

    var real = new FooClass();
    Test(() => real.Execute());                   // benchmark, direct call

    var type = res.CompiledAssembly.GetType("FooClass");
    var obj = Activator.CreateInstance(type);    
    var method = type.GetMethod("Execute");
    var input = new object[] { };                
    Test(() => (int)method.Invoke(obj, input));   // reflection invoke  

    dynamic dyn = Activator.CreateInstance(type);  
    Test(() => dyn.Execute());                    // dynamic object invoke

    var action = (Func)Delegate.CreateDelegate(typeof(Func), null, method); 
    Test(() => action());                         // delegate
}

The results are:

8     // direct
771   // reflection invoke
41    // dynamic object invoke
7     // delegate

So in those cases where you can't use delegates (if you don't know enough?), you can try dynamic.