Clash Royale CLAN TAG#URR8PPP

Is static extern void Buffer.InternalBlockCopy part of .NET Framework?

I study how FileStream is implemented in C# and in the Read(..) method I can see:

n = ReadCore(_buffer, 0, _bufferSize);
...
Buffer.InternalBlockCopy(_buffer, _readPos, array, offset, n);
...


Where Buffer.InternalBlockCopy points to definition (bellow) in buffer.cs. The method BlockCopy is defined as static extern. Where is this method defined? It is part of .NET? It is managed or native?

[System.Runtime.InteropServices.ComVisible(true)]
public static class Buffer

// Copies from one primitive array to another primitive array without
// respecting types. This calls memmove internally. The count and
// offset parameters here are in bytes. If you want to use traditional
// array element indices and counts, use Array.Copy.
[System.Security.SecuritySafeCritical] // auto-generated
[ResourceExposure(ResourceScope.None)]
[MethodImplAttribute(MethodImplOptions.InternalCall)]
public static extern void BlockCopy(Array src, int srcOffset,
Array dst, int dstOffset, int count);
..



1 Answer
1

Well, the extern keyword means that the method is defined outside C# code, and the

extern

[MethodImplAttribute(MethodImplOptions.InternalCall)]


means that it calls a method defined inside Common Language Runtime.

After MethodImplOptions docs:

MethodImplOptions

The call is internal, that is, it calls a method that is implemented within the common language runtime.

By clicking "Post Your Answer", you acknowledge that you have read our updated terms of service, privacy policy and cookie policy, and that your continued use of the website is subject to these policies.