Fix copy-paste error method-parameters.md

[andre1110]

When you assign new instance to the value type paramenter by reference, the changes are visible from the caller method

var instance = new TestStruct { Property = 0 };
AssignNewInstance(ref instance);
Console.WriteLine(instance.Property);
// 42

void AssignNewInstance(ref TestStruct local)
{
    local = new TestStruct { Property = 42 };
    return;
}
struct TestStruct
{
    public int Property { get; set; }
}

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[BillWagner]

Hi @andre1110

The current text is actually correct (although it could use some further clarification). See my notes in #32853

[andre1110]

Hello @BillWagner
I tend to think that you are wrong for 2 reasons:

1. Your code snippet in Pass a value type by reference: assigning the parameter to refer to a different object (learning.microsoft.com) #32853 demonstrates 'ref assignment' and not 'assignment' per se. IMHO when reading the sentence If the method assigns the parameter to refer to a different object I can only naturally imagine the code similar to what I pasted in the original post.
2. If we assume you are correct, then the same 'ref assignment' for a reference type instance should yield different results according to the documentation: When you pass a reference type by reference: If the method assigns the parameter to refer to a different object, those changes are visible from the caller. However, in fact, it does not:

   static MyClass staticInstance = new MyClass { Id = 5 };
   
   var localInstance = new MyClass { Id = 3 };
   AssignNewMyClass(ref localInstance);
   Console.WriteLine("The value outside of the method: {0}", localInstance);
   // The value outside of the method: 3
   
   static void AssignNewMyClass(ref MyClass x){
       x = ref staticInstance;
       Console.WriteLine("The value inside the method: {0}", x);
       // The value inside the method: 5
   }
   
   class MyClass
   {
       public int Id { get; set; }
       public override string ToString() => Id.ToString();
   }