How to convert a unmanaged pointer, thats pointing to an array of COLORREFS, into a managed array of UInt32 in C#?

I'm trying to write a .dll and then call this .dll in C#.

Now, I have the problem of how can I convert the unmanaged pointer, thats pointing to an array of COLORREFS, into a managed array of UInt32 in C#?

Or is there a better approach?

This is the function from the .dll implemented in a header file:

COLORREF results[10]{ CLR_INVALID }; //<-- First try, dynamic array size is the ultimate goal.

__declspec(dllexport) COLORREF* __stdcall getColorArea(int tlX, int tlY, int brX, int brY) {
 HDC _hdc = GetDC(NULL);
 if (_hdc)
 {
   int _x = tlX;
   int _y = tlY;
   int _count = 0;
   while (_x <= brX) 
    {
      if (_y != tlY) { _y = tlY; }

      while (_y <= brY)
      {
        results[_count] = GetPixel(_hdc, _x, _y);
        _count++;
        _y++;
      }
      _x++;
    }
    ReleaseDC(NULL, _hdc);
    return results;
  }
  return results;
}

And here are some parts from the C# source:

[DllImport(@"test.dll", EntryPoint = "getColorArea", CallingConvention = CallingConvention.StdCall)]
unsafe extern static UInt32* getColorArea(int ltX, int ltY, int rbX, int rbY);

unsafe private void GetSetColor(int ltx, int lty, int rbx, int rby) {
  int _count = 0;
  //Array.Copy(_result, _res, 10); //<-- I tried some variations but nothing worked.
  UInt32* _result = getColorArea(ltx, lty, rbx, rby);
  foreach (Control _c in this.ColorDisplay.Controls)
    {
      if (_result[_count] != 0xFFFFFFFF)
      {
        _c.BackColor = ColorTranslator.FromWin32((int)_result[_count]);
        _count++;
      }
    }
}   // It throws no exception but sets in the end only 4 from 10 Controls.