在c ++中我有这样的功能
extern "C" _declspec(dllexport) uint8* bufferOperations(uint8* incoming, int size)
我试图从c#中调用它,就像这个
[DllImport("MagicLib.DLL", CallingConvention = CallingConvention.Cdecl)]
//[return: MarshalAs(UnmanagedType.ByValArray)]//, ArraySubType=UnmanagedType.SysUInt)]
public static extern byte[] bufferOperations(byte[] incoming, int size);
但我得到了 无法编组“返回值”:无效的托管/非托管类型组合
<(>((问题是 - 如何正确编组? 感谢您阅读我的问题答案 0 :(得分:9)
byte []是一个已知长度的.Net数组类型。你不能编组字节*,因为.Net不知道输出数组的长度。你应该尝试手动编组。将byte []替换为byte *。然后,这样做:
[DllImport("MagicLib.DLL", CallingConvention = CallingConvention.Cdecl)]
public static extern byte* bufferOperations(byte* incoming, int size);
public void TestMethod()
{
var incoming = new byte[100];
fixed (byte* inBuf = incoming)
{
byte* outBuf = bufferOperations(inBuf, incoming.Length);
// Assume, that the same buffer is returned, only with data changed.
// Or by any other means, get the real lenght of output buffer (e.g. from library docs, etc).
for (int i = 0; i < incoming.Length; i++)
incoming[i] = outBuf[i];
}
}
答案 1 :(得分:1)
在这种情况下,您无需使用def array123(nums):
for i in range(len(nums)):
if nums[i:i+3] == [1,2,3]:
return True
return False
。只需使用IntPtr。
unsafe contexts
然后你可以使用Marshal.Copy从中获取你的字节数组。