有几种方法可以访问与字节数组相对应的 IntPtr。
第一种是使用不安全的代码块来访问直接指向字节数组的指针。
//C#
unsafe
{
byte[] test = new byte[5];
fixed (byte* p = &test[0])
{
*p = 0xff;
}
}
也可以使用 GCHandle 来获得对象。
//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，可以这样实现：通过 LocalAlloc 创建内存块并将数据封送处理到该内存块。
//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);
}