How can I pin an array of byte?

Question

I want to pin an array of bytes which is 10 megabytes long so that managed and unmanaged code can work on it.

My scenario is that I have an unmanaged driver which re

Answer 1

There are 2 ways to do this. The first is to use the fixed statement:

unsafe void UsingFixed()
{
    var dataArray = new byte[10*1024*1024];
    fixed (byte* array = dataArray)
    {
        // array is pinned until the end of the 'fixed' block
    }
}

However, it sounds like you want the array pinned for a longer period of time. You can use GCHandles to accomplish this:

void UsingGCHandles()
{
    var dataArray = new byte[10*1024*1024];
    var handle = GCHandle.Alloc(dataArray, GCHandleType.Pinned);

    // retrieve a raw pointer to pass to the native code:
    IntPtr ptr = handle.ToIntPtr();

    // later, possibly in some other method:
    handle.Free();
}