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我无法让代码在托管环境中工作（VS2008 C++/CLI Win Forms App）。问题是我不能在托管代码中声明非托管结构（这甚至可能吗？），所以我已经声明了一个托管结构，但现在我遇到了如何将字节从缓冲区复制到该结构的问题。这是显然可以按预期工作的纯 C++ 代码：

typedef struct GPS_point {
  float point_unknown_1;
  float latitude;
  float longitude;
  float altitude;            // x10000
  float time;
  int point_unknown_2;
  int speed;                 // x100
  int manually_logged_point; // flag (1 --> point logged manually)
  } track_point;

int offset           = 0;
int filesize         = 256;  // simulates filesize
int point_num        = 10;   // simulates number of records

int main () {

char *buffer_dyn = new char[filesize];  // allocate RAM
// here, the file would have been read into the buffer
buffer_dyn[0xa8] = 0x1e;  // simulates the speed data (1e 00 00 00)
buffer_dyn[0xa9] = 0x00;
buffer_dyn[0xaa] = 0x00;
buffer_dyn[0xab] = 0x00;

offset = 0x90;  // if the data with this offset is transfered trom buffer
                // to struct, int speed is alligned with the buffer at the
                // offset of 0xa8

track_point *points = new track_point[point_num];
points[0].speed    = 0xff;  // (debug) it should change into 0x1e
memcpy(&points[0],buffer_dyn+offset,32);

cout << "offset: " << offset << "\r\n";
//cout << "speed: " << points[0].speed << "\r\n";
printf ("speed : 0x%x\r\n",points[0].speed);
printf("byte at offset 0xa8: 0x%x\r\n",(unsigned char)buffer_dyn[0xa8]);  // should be 0x1e

delete[] buffer_dyn;  // release RAM
delete[] points;

/*
What I need is to rewrite the lines 29 and 31 to work in the managed code (VS2008 Win Forms C++/CLI)
What should I have after:

array<track_point^>^ points = gcnew array<track_point^>(point_num);

so I can copy 32 bytes from buffer_dyn to the managed struct declared as

typedef ref struct GPS_point {
  float point_unknown_1;
  float latitude;
  float longitude;
  float altitude;             // x10000
  float time;
  int point_unknown_2;
  int speed;                  // x100
  int manually_logged_point;  // flag (1 --> point logged manually)
  } track_point;
*/

return 0;
}

这是codepad.org的粘贴，因此可以看到代码是可以的。

我需要的是重写这两行：

track_point *points = new track_point[point_num];
memcpy(&points[0],buffer_dyn+offset,32);

可以在托管应用程序中工作的东西。我写：

array<track_point^>^ points = gcnew array<track_point^>(point_num);

现在我正在尝试通过结构从缓冲区复制所描述的数据复制，但不知道应该如何完成。

或者，如果有一种方法可以以我的代码中显示的相同方式使用非托管结构，那么我想避免使用托管结构。

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