CSharp超大数组的解决方案

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public class LongArray<T> : IDisposable where T : struct
{
    private IntPtr _head;
    private Int64 _capacity;
    private UInt64 _bytes;
    private Int32 _elementSize;

    public LongArray(long capacity)
    {
        if (_capacity < 0) throw new ArgumentException("The capacity can not be negative");
        _elementSize = SizeOf(default(T));
        _capacity = capacity;
        _bytes = (ulong)capacity * (ulong)_elementSize;
        _head = AllocHGlobal((IntPtr)_bytes);
    }

    public T this[long index]
    {
        get
        {
            IntPtr p = _getAddress(index);
            T val = (T)System.Runtime.InteropServices.Marshal.PtrToStructure(p, typeof(T));
            return val;
        }
        set
        {
            IntPtr p = _getAddress(index);
            StructureToPtr(value, p, true);
        }
    }

    protected bool disposed = false;
    public void Dispose()
    {
        if (!disposed)
        {
            FreeHGlobal((IntPtr)_head);
            disposed = true;
        }
    }

    public IntPtr _getAddress(long index)
    {
        if (disposed) 
            throw new ObjectDisposedException("Can't access the array once it has been disposed!");
        if (index < 0) 
            throw new IndexOutOfRangeException("Negative indices are not allowed");
        if (!(index < _capacity)) 
            throw new IndexOutOfRangeException("Index is out of bounds of this array");
        return (IntPtr)((ulong)_head + (ulong)index * (ulong)(_elementSize));
    }
}