有幾種方法可以訪問與字節數組相對應的 IntPtr。
第一種是使用不安全的代碼塊來訪問直接指向字節數組的指針。
//C#
unsafe
{
byte[] test = new byte[5];
fixed (byte* p = &test[0])
{
*p = 0xff;
}
}
也可以使用 GCHandle 來獲得對象。
//C#
using System.Runtime.InteropServices;
byte[] test = new byte[5];
GCHandle hObject = GCHandle.Alloc(test, GCHandleType.Pinned);
IntPtr pObject = hObject.AddrOfPinnedObject();
if(hObject.IsAllocated)
hObject.Free();
最后，可以這樣實現：通過 LocalAlloc 創建內存塊並將數據封送處理到該內存塊。
//C#
[DllImport("coredll.dll",SetLastError=true)]
public static extern IntPtr LocalAlloc(uint uFlags, uint uBytes);
[DllImport("coredll.dll",SetLastError=true)]
public static extern IntPtr LocalFree(IntPtr hMem);
[DllImport("coredll.dll",SetLastError=true)]
public static extern IntPtr LocalReAlloc(IntPtr hMem, uint uBytes, uint fuFlags);
public const uint LMEM_FIXED = 0;
public const uint LMEM_MOVEABLE = 2;
public const uint LMEM_ZEROINIT = 0x0040;
byte[] test = new byte[5];
IntPtr p = LocalAlloc(LMEM_FIXED | LMEM_ZEROINIT, (uint)test.Length);
if (p == IntPtr.Zero)
{
throw new OutOfMemoryException();
}
else
{
Marshal.Copy(test, 0, p, test.Length);
}