MethodInfo.Invoke and reading ref parameters

[ian]

Hi,

I can't find a solution to this, so I've brought it to the experts.
Using reflection I can get a MethodInfo object pointing at an assembly's
method.
Where I have a MethodInfo object pointing at a function, say func(int
p1, ref int p2), how do I read p2 after a successful invocation?
I've tried interogating the parameterinfo objects on the method, I've
seen some hints about overriding something or casting some other object
type to an array of objects, but no concrete examples, not even some
sand ones!

Thank you

 

[Barry Kelly]

I can't find a solution to this, so I've brought it to the experts.
Using reflection I can get a MethodInfo object pointing at an assembly's
method.
Where I have a MethodInfo object pointing at a function, say func(int
p1, ref int p2), how do I read p2 after a successful invocation?

The object array you pass to Invoke() gets modified, and the value
returned is put in the correct location in the array.

I've tried interogating the parameterinfo objects on the method, I've
seen some hints about overriding something or casting some other object
type to an array of objects, but no concrete examples, not even some
sand ones!

---8<---
using System;
using System.Reflection;

class App
{
static void Main()
{
MethodInfo doubleInt = typeof(App).GetMethod("DoubleInt",
BindingFlags.NonPublic | BindingFlags.Static);
object[] args = { 21 };
doubleInt.Invoke(null, args);
Console.WriteLine(args[0]);
}

static void DoubleInt(ref int x)
{
x = x * 2;
}
}
--->8---

-- Barry