Parameter passing to Invoke method

[KK]

Hi MCPP gurus'
I have a small problem in parameter passing.This is my situation

namespace Abc
{
public __gc class ClassAbc
{
public:
String* Hello(String* str)
{
return String::Concat(S"Hello ",str);
}
String* HelloAbc(String** str)
{
*str = new String("Created inside Assembly");
return String::Concat(S"Hello ",*str);
}
};
}
I want to invoke HelloAbc method of class ClassAbc using MethodInfo-Invoke
method?
Can anybody help me how to pass parameters to this situation?Can any body
lead me to a link which explains how to pass different kind of
parameters(arrays,reference to objects pointers)to the Invoke method?

Thanks a Lot
regards
Krishna