我正在尝试从C#中使用C++ dll中的函数,但是我遇到了错误:“尝试读取或写入受保护的内存。这通常表示其他内存已经损坏”
有人知道如何解决吗?
这是C++函数:
typedef void *DGNHandle;
__declspec(dllexport) DGNHandle CPL_DLL DGNOpen( const char *, int );
__declspec(dllexport) DGNElemCore CPL_DLL *DGNReadElement( DGNHandle )
以下是C++中的结构体:
typedef struct {
int offset;
int size;
int element_id; /*!< Element number (zero based) */
int stype; /*!< Structure type: (DGNST_*) */
int level; /*!< Element Level: 0-63 */
int type; /*!< Element type (DGNT_) */
int complex; /*!< Is element complex? */
int deleted; /*!< Is element deleted? */
int graphic_group; /*!< Graphic group number */
int properties; /*!< Properties: ORing of DGNPF_ flags */
int color; /*!< Color index (0-255) */
int weight; /*!< Line Weight (0-31) */
int style; /*!< Line Style: One of DGNS_* values */
int attr_bytes; /*!< Bytes of attribute data, usually zero. */
unsigned char *attr_data; /*!< Raw attribute data */
int raw_bytes; /*!< Bytes of raw data, usually zero. */
unsigned char *raw_data; /*!< All raw element data including header. */
} DGNElemCore;
以下是转换后的C#代码:
[StructLayout(LayoutKind.Sequential )]
public class DGNElemCore
{
public int attr_bytes;
public byte[] attr_data;
public int color;
public int complex;
public int deleted;
public int element_id;
public int graphic_group;
public int level;
public int offset;
public int properties;
public int raw_bytes;
public byte[] raw_data;
public int size;
public int style;
public int stype;
public int type;
public int weight;
}
[DllImport("DgnLib.dll", EntryPoint = "DGNOpen")]
public static extern IntPtr DGNOpen(string fileName, int bUpdate);
[DllImport("DgnLib.dll", EntryPoint = "DGNReadElement")]
public static extern DGNElemCore DGNReadElement(IntPtr DGNHandle)
测试代码:
DGNElemCore element = new DGNElemCore();
element = DgnFile.DGNReadElement(dgnFile.oDgnFile) **//Throw error**