VB或VB.net中怎么调用DLL中的结构体参数

VB或VB.net中如何调用DLL中的结构体参数
最近做一下USB视频采集卡开发，DLL中的录像操作比较复杂，其中有结构体一个函数一直没调好，网上这类的贴子挺多，试了好多次也没试好！
VC声明

C/C++ code

typedef enum{    VIDEO_ENCORE_CBR = 0,    VIDEO_ENCORE_VBR = 1,}ENCOREMODE;typedef struct _tagMediaParam{    ENCOREMODE     enEncoreMode;    double        dbFrameRate;    DWORD        dwVideoWidth;    DWORD          dwVideoHeight;    DWORD          dwBitRate;    DWORD          dwVBRPeakRate;    DWORD          dwVBRMaxRate;    DWORD          dwQuantizer;    DWORD        dwMotionPrecision;    DWORD          dwKeyFrmInterval;}VIDEO_ENCORE_PARAM,*PVIDEO_ENCORE_PARAM;typedef enum{    RECTYPE_MP4 = 0,    RECTYPE_AVI = 1,}RECTYPE;HYUTIL_API UINT WINAPI HYCreateEncoder(UINT unIndex,UINT unRequestFlag,PVIDEO_ENCORE_PARAM pVideoEncoreParam);HYUTIL_API UINT WINAPI HYCreateRecordFile(UINT unIndex,LPCTSTR szFileName,RECTYPE enType);

VC中使用

C/C++ code

    UINT unRet  = HYCreateEncoder(m_nDevIndex,unFlag,&m_VideoEncore);    HYCreateRecordFile(m_nDevIndex,szFile,enType)

我在VB中的声明

VB code

    Type tagMediaParam        enEncoreMode As Integer        dbFrameRate As Double        dwVideoWidth As Long        dwVideoHeight As Long        dwBitRate As Long        dwVBRPeakRate As Long        dwVBRMaxRate As Long        dwQuantizer As Long        dwMotionPrecision As Long        dwKeyFrmInterval  As Long    End Type        '开始/停止媒体数据编码    Public Declare Function HYCreateEncoder Lib "HYUtil.DLL" (ByVal unIndex As Integer, ByVal unRequestFlag As Integer, pVideoEncoreParam As tagMediaParam) As Integer   Public Declare Function HYCreateRecordFile Lib "HYUtil.DLL" (ByVal unIndex As Integer, ByVal szFileName As String, enType As Integer) As Integer 

VB中使用，但一直提示出错： 无效的函数调用参数

VB code

Dim sFile As StringsFile = "d:\a.avi"Dim pVE As tagMediaParampVE.dwBitRate = 25pVE.dwVideoWidth = 720pVE.dwVideoHeight = 576xx = HYCreateEncoder(0, 0, pVE)    '这个函数出错  无效的函数调用参数xx = HYCreateRecordFile(0, sFile, 1)

[解决办法]
在C, C++中UINT 相当于VB中的LONG
你把所有Integer 改成LONG试试
[解决办法]
上面还有个ENCOREMODE 数据类型。定义了木有
[解决办法]

探讨

typedef enum
{
VIDEO_ENCORE_CBR = 0,
VIDEO_ENCORE_VBR = 1,
}ENCOREMODE;
这在VB中应该用什么类型呀，VC里也没指明类型，我觉得就用integer就行，这是个枚举，也不是结构体，应该不是两个参数，是一个参数

[解决办法]
1.函数声明中把 pVideoEncoreParam As tagMediaParam 这个改成byval pVideoEncoreParam As tagMediaParam 值传递试试
2.不行的话把xx = HYCreateEncoder(0, 0, pVE)
改成xx = HYCreateEncoder(0, 0, varptr(pVE))
或改成xx = HYCreateEncoder(0, 0,byval varptr(pVE))