怎样 import 这个函数

[32757487]

方法：
MT_RESULT MTGetAdapterInfo(const BOARD nboard,PMTADAPTER_INFO const pBoardInfo,PULONG const pLength);

参数说明：
nboard ：board number
pBoardInfo ：pointer to MTADAPTER_INFO structure
pLength ：Set by the user application, this is a pointer to the size of the given buffer
for the MTADAPTER_INFO structure.

Structure定义说明：
MTADAPTER_INFO structure is defined as follows:
public struct MTADAPTER_INFO
{
ulong Status; // Status value of BOARD_OK, etc.
ulong BoardNumber; // Board index in SDK, i.e. SystemIndex
MT_VERSION FWVersion; // On board firmware version
ulong BaseAddress; // I/O base address
ulong Interrupt; // Interrupt number
ulong StartChannel; // Logical # of the 1st on board channel
ulong Channels; // Number of channels on the board
ulong Option1; // Basic Board option
// option 1
// bit 0 WAV
// bit 1 MVIP
// bit 2 Volume/Pitch
// bit 3 MF
// bit 4 Silence Compression
ulong Option2; // Extended Board option
// option 2
// bit 0 Caller ID
// bit 1 Conference
// bit 2 Call Logging
// bit 4 FAX
// bit 6 Pulse detection
ulong Digirate; // Digitizing rate
ulong Bandwidth; // Channel bandwidth
ulong PCISlot;
ulong PCIBusNumber;

ulong BoardType; // Board Type of DUAL_T1_PASSIVE_HI_CARD, etc.

UCHAR BusType; // MUX_H100, MUX_MVIP, or MUX_NONE
UCHAR MasterMode; // Board Master Mode of the following:
// 0 slave board
// 1 MVIP master, or H100 Master A
// 2 H100 Master B
UCHAR MasterClock; // Master clock source reference value
// of CLOCK_SOURCE_OSC, and etc.
UCHAR Sec8kNetrefClock; // MVIP Sec8K or H100 Netref clock output
// 0 Disabled, output tri-stated
// 1, 3 - 4 Type of clock reference of
// CLOCK_SOURCE_OSC, etc.
UCHAR NumSummations; // Number of summation resource on board, if any
UCHAR StartSummation; // Index of the first on board summation resource
UCHAR NumAudios; // Number of audio jack resource on board, if any
UCHAR StartAudio; // Index of the first on board audio jack resource
UCHAR TDMSignaling; // CT TDM bus signaling: 0 for u-law, 1 for A-law
UCHAR ConfigurationId; // Adapter Configuration Index (i.e. SwitchIndex)
UCHAR res[2];
MT_VERSION FWVersionExpected; // Expected on board firmware version
}

函数返回值：
MT_RET_OK No error
MT_RET_INVALID_PARAM Invalid argument passed to function
MT_RET_INVALID_BOARD Board number is out of range
MT_RET_NOT_AVAILABLE Driver is not loaded


我想知道的问题是：
1，他的返回值是自定的key值(.h中的定义之一：#define MT_RET_INVALID_PARAM 0xE0002012L)，我应该用什么托管类型来与之对应？
2，他所有的自定义类型我都必须建立与之对应的托管版本么？
3，”a pointer to the size of the given buffer“ 这个buffer我应该用什么托管类型代替？
4，哪里有专题的非托管到托管类型包装的的讨论？


谢谢

[Knight94]

至于返回值类型，你可以用enum来定义，如下：
public enum MT_RESULT:long
{
MT_RET_INVALID_PARAM = 0xE0002012L,
}

[32757487]

谢谢
马上开工试验~

[32757487]

嗨
这里还有其他一些windows内自己定义的数据类型,我如何使用啊:
PVOID
LARGE_INTEGER

[32757487]

下边这个Struct内
（已经修改为managed版本，除了两个winnt 数据类型：LARGE_INTEGER PVOID):

public struct MT_EVENT
{

LARGE_INTEGER TimeStamp; // In FILETIME format
public uint UserStatus; // Not used by API
public uint EventCode; // Event Code
public uint SubReason; // Event sub-reason
public uint XtraInfo; // Extra information, e.g. termination
public uint FuncCode; // Function active when this event occurred
public UInt16 Board; // Board ID
public UInt16 Channel; // Global Channel ID (GCI)
PVOID ptrBuffer; // Related play/record buffer pointer
public uint DataLength; // Byte length of data accessed (played/recorded)

PVOID ptrXtraBuffer; // Pointer to xtra buffer
public uint XtraBufferLength; // Length of buffer pointed by ptrXtraBuffer
public uint XtraDataLength; // Length of data in buffer pointed by ptrXtraBuffer
public uint EventFlag; // Falgs of the following:
// bit 0x00000001: 1 - Appl created the event
// 0 - NTi DLL created the event
// bit 0x00000002: 1 - Appl allocated ptrtraBuffer
// 0 - NTi DLL allocated ptrXtraBuffer
};

[Knight94]

to PVOID
简单点儿，就是IntPtr，如果不想用IntPtr，看看这个类型具体指向什么类型内容；

to LARGE_INTEGER
看其字节个数，
4 bytes : int or Int32
8 bytes : Int64

[32757487]

hi ,老大
我按照你的提示做，得到提示

can not marshal filed associatedts of type chan_ts :this type can not be marshaled as structure filed.





tell me why and how to solve it please.

thks a lot....

[Knight94]

你是编译不通过，还是运行呢

[32757487]

运行的时候

[Knight94]

Sample code as follows:
public struct chan_info
{
public uint type;
[MarshalAs(UnmanagedType.LPArray, SizeConst=2)]
public chan_ts[] associatedts;
public chan_info( uint typevalue )
{
type = typevalue;
associatedts = new chan_ts[2];
for( int i = 0; i < 2; i++ )
associatedts[i] = new chan_ts();
}
}

public struct chan_ts
{
public short id;
public short name;
}

[Knight94]

//calling
chan_info mychan_info = new chan_info( 1 );
MessageBox.Show( mychan_info.type.ToString() );
MessageBox.Show( mychan_info.associatedts[0].ToString() );
MessageBox.Show( mychan_info.associatedts[1].ToString() );

[32757487]

还是一样~

[32757487]

老大，我太弱,急，没时间允许我慢慢找，直接问您了
还有问题：

方法：
MtGetInfor（
const channel，//ulong channel number
PMTCHAN_INFO const pchannel_info,//a pointer to chan_info structure
PULONG CONST plength //a pointer to the size of the gaven buffer for the chan_info structure
）
structure:
typpedef struct chan_info
{
ulong type;
chan_ts associatedts[2] //结构数组，这玩意怎么搞？
}
typedef struct chan_ts
{
short id;
short name;
}
想知道:
1,方法里第二个参数是structure pointer，我传得是 ref structure ok?
2,structure[] 要怎么弄？

[Knight94]

to 1,方法里第二个参数是structure pointer，我传得是 ref structure ok?

可以

to 2
[MarshalAs(UnmanagedType.LPArray, SizeConst=2)]chan_ts[] associatedts;

[32757487]

1
数组都用MarshalAs(UnmanagedType.LPArray, SizeConst=n)这样的模式
而不用管它是什么类型的么？

2

上边的函数第二个参数是个pointer，最后那个参数是pionter to size of given buffer for ...
有些问题，这个pointer到底是指向buffer 还是指向buffer的size

我又该给他传个啥？

谢谢

[Knight94]

to PULONG CONST plength //a pointer to the size of the gaven buffer for the chan_info structure

ref int Length

[32757487]

为什么？
Structure里包含还有Strucrure[] 就不能Marshal....

怎么解决阿

[Knight94]

to Structure里包含还有Strucrure[] 就不能Marshal....

所出现问题的dll函数是什么样的

[32757487]

查了相关资料
好像c#对c-style arry的支持不很好,好像仅ByValArry有用。

出问题的dll函数需要一个上边的自定义的structure的pionter 参数，
刚好，这个structure里又有structure数组

我现在参考别人的做法，把这个field ：stucture[]替换成等同长度[bit位]的byte
上边这个长度是
typpedef struct chan_info
{
ulong type; //32
chan_ts associatedts[2] //16*4
}
typedef struct chan_ts
{
short id; //16bit
short name; //16bit
}

替换成如下：

public struct chan_info
{
pubic uint type;
[MarshalAs(UnmanagedType.ByValArry,ConstSize=4)//4 byte
public byte[];
}

[32757487]

竟然出现 null object reference exception；

[Knight94]

to 竟然出现 null object reference exception；

如何使用的，你需要在chan_info写一个构造函数，来初始化数组。