public static unsafe IDisposable ChangeArrayType(Array array, Int32 oldElementSize, out void *pointer)
{
if (array.Length < 1)
{
throw new NotSupportedException();
}
SafeGCHandle handle = new SafeGCHandle(array, GCHandleType.Pinned);
try
{
pointer = handle.AddrOfPinnedObject().ToPointer();
UIntPtr *arrayPointer = (UIntPtr *)pointer;
UIntPtr arrayLength = *(arrayPointer - 1);
UIntPtr arrayType = *(arrayPointer - 2);
UInt64 arraySize = ((UInt64)arrayLength * (UInt64)oldElementSize);
if (arraySize % (UInt64)UnsafeSize != 0)
{
throw new InvalidCastException();
}
try
{
*(arrayPointer - 1) = new UIntPtr(arraySize / (UInt64)UnsafeSize);
*(arrayPointer - 2) = ArrayTypePointer;
return(new DisposableAction(() =>
{
*(arrayPointer - 1) = arrayLength;
*(arrayPointer - 2) = arrayType;
handle.Dispose();
}));
}
catch
{
*(arrayPointer - 1) = arrayLength;
*(arrayPointer - 2) = arrayType;
throw;
}
}
catch
{
handle.Dispose();
throw;
}
}
private static unsafe UIntPtr GetArrayTypePointer()
{
T[] result = new T[1];
using (SafeGCHandle handle = new SafeGCHandle(result, GCHandleType.Pinned))
return(*(((UIntPtr *)handle.AddrOfPinnedObject().ToPointer()) - 2));
}