Pointer Library for All .NET Languages (written in MSIL)

• Download UnsafeLibrary.zip - 5.7 KB

Introduction

This library is designed to allow users of all .NET languages to be able to use pointers without trouble, just like those using C# or C++. Of course, it will be at the user's own risk.

Using the code

I was bothered by the fact that pointers (and related operations) can only be accessed in C# and C++, and that they only work on unmanaged types. I then decided to make a library which would overcome this, because (a) certain P/Invoke methods need it, (b) because languages other than C++ and C# do not support pointers, and (c) because the pointer structure is now strongly typed.

Just beware that using the Marshal class may be more accurate than this library, because the methods are for managed types (before marshaling). I noticed this only after I made the library. But, hey, if it works, use it!

Points of Interest

The method ManagedSizeOf<T>() returns the same thing as saying sizeof(T) in C#, only that it is not restricted to unmanaged types - if T is a reference type, it returns the size of the reference (which on x86 computers seems to be 4 bytes). If T is a value type, it returns the size of that type, whether or not it is managed. The reason that I called put the work Managed in front of it was to indicated that it returns the size of the type BEFORE marshaling, unlike Marshal.SizeOf().

The ManagedSizeOf(System.Type type) method uses Reflection to call the other ManagedSizeOf method, while substituting T with the type. Therefore, it is inherently slower than the previous method and should be used with care.

The GetAddressOf<T>(ref T obj) method returns the address of that variable, whether or not it is a reference type.

The Pointer<T> structure encapsulates a variable of type T* which can be indexed like normal pointers (like ptr[9]), as well as converted to System.IntPtr and other formats. If the language supports pointers (like in C#), then the pointer field can be directly used. Otherwise, the indexing and other properties must be used or it can be converted to a System.IntPtr.

Here is a bug I found, but do not know how to fix (any suggestions are appreciated):
On one computer (on which I was not an Administrator), a test program was run. However, a VerificationException occured before entering Main because the runtime could not verify the code in UnsafeLibrary.dll. I only saw this error once.

This program may have bugs.. don't rely on it being correct! Tell me if you find any. I am still not sure whether the AddressOf method works correctly all the time, because I do not know whether it returns the address of the ref parameter or a copy of it.