c++转变为c#的代码怎么实现（在线急等）

Question

BOOL WINAPI FaxSendDocument(
  HANDLE FaxHandle,          // handle to the fax server
  LPCTSTR FileName,          // file with data to transmit
  PFAX_JOB_PARAM JobParams,  // pointer to job information structure
  CONST FAX_COVERPAGE_INFO *CoverpageInfo OPTIONAL, 
                             // pointer to local cover page structure
  LPDWORD FaxJobId           // fax job identifier
);因为*CoverpageInfo可以为null，所有想转成IntPtr类型，请问怎么转为IntPtr类型？

Answer 1

[DllImport("winfax.dll", SetLastError = true)]
static extern bool FaxSendDocument (IntPtr FaxHandle, string FileName,
   ref FAX_JOB_PARAM JobParams, ref FAX_COVERPAGE_INFO CoverpageInfo,
   ref uint FaxJobId);//If you use FAX_JOB_PARAM and FAX_COVERPAGE_INFO as a CLASS !
[DllImport("winfax.dll", SetLastError = true)]
[DllImport(DLLWinFax, SetLastError = true)]
static extern bool FaxSendDocument(IntPtr FaxHandle, string FileName,
FAX_JOB_PARAM JobParams, FAX_COVERPAGE_INFO CoverpageInfo,
  out uint FaxJobId);

Answer 2

谢谢楼上的，我现在是这样的
[DllImport("winfax.dll", SetLastError=true)]
public static extern bool FaxSendDocument(int FaxHandle, string FileName, 
[In] ref FAX_JOB_PARAM JobParams, [In] ref FAX_COVERPAGE_INFO CoverpageInfo,
[Out] out int FaxJobId);
但是platform文档里说
CoverpageInfo 
[in] Pointer to a FAX_COVERPAGE_INFO structure that contains personal data to display on the cover page of the fax document. This parameter must be NULL if a cover page is not required. 所以我想穿一个null给他，但是老是报参数不对。系统错误编号为87（The parameter is incorrect.）
IntPtr coverPageNull = ((IntPtr)((int)(0)));
if(!FaxSendDocument(hFax, faxDocument, ref jobParam, ref coverPageNull, out faxJobID))

Answer 3

int coverPageNull = 0;
if(!FaxSendDocument(hFax, faxDocument, ref jobParam, ref coverPageNull, out faxJobID))

Answer 4

你把FAX_COVERPAGE_INFO的定义方式由struct改为class，然后用null就行了。

Answer 5

ref FAX_COVERPAGE_INFO CoverpageInfo
这个 FAX_COVERPAGE_INFO 类型能不能能null值?

Answer 6

我还是把原代码给你们看看，你们帮我调调
using System;
using System.Runtime.InteropServices;
public abstract class Win32
{
public static readonly int INFINITE = -1;
public static readonly int INVALID_HANDLE_VALUE = -1; [DllImport("kernel32")]
public static extern int CreateIoCompletionPort(int FileHandle, int ExistingCompletionPort, 
int CompletionKey, int NumberOfConcurrentThreads); [DllImport("kernel32")]
public static extern int GetQueuedCompletionStatus(int CompletionPort, 
ref int lpNumberOfBytesTransferred, ref int lpCompletionKey, IntPtr lpOverlapped, 
int dwMilliseconds); [DllImport("kernel32")]
public static extern int CloseHandle(int hObject);
}public abstract class WinFax
{
#region member
// private const IntPtr NullPtr = ((IntPtr)((int)(0)));
// [CLSCompliant(false)]
// unsafe IntPtr Null = new IntPtr( void* value ); #endregion
#region Enumerations public enum FAX_PORT_OPEN_TYPE
{
PORT_OPEN_QUERY = 1,
PORT_OPEN_MODIFY = 2
} public enum FAX_ENUM_JOB_SEND_ATTRIBUTES
{
JSA_NOW = 0, // Send now
JSA_SPECIFIC_TIME, // Send at specific time
JSA_DISCOUNT_PERIOD // Send at server configured discount period
} [FlagsAttribute()]
public enum WinFaxEvent
{
FEI_DIALING = 0x00000001,
FEI_SENDING = 0x00000002,
FEI_RECEIVING = 0x00000003,
FEI_COMPLETED = 0x00000004,
FEI_BUSY = 0x00000005,
FEI_NO_ANSWER = 0x00000006,
FEI_BAD_ADDRESS = 0x00000007,
FEI_NO_DIAL_TONE = 0x00000008,
FEI_DISCONNECTED = 0x00000009,
FEI_FATAL_ERROR = 0x0000000a,
FEI_NOT_FAX_CALL = 0x0000000b,
FEI_CALL_DELAYED = 0x0000000c,
FEI_CALL_BLACKLISTED = 0x0000000d,
FEI_RINGING = 0x0000000e,
FEI_ABORTING = 0x0000000f,
FEI_ROUTING = 0x00000010,
FEI_MODEM_POWERED_ON = 0x00000011,
FEI_MODEM_POWERED_OFF = 0x00000012,
FEI_IDLE = 0x00000013,
FEI_FAXSVC_ENDED = 0x00000014,
FEI_ANSWERED = 0x00000015,
FEI_JOB_QUEUED = 0x00000016,
FEI_DELETED = 0x00000017,
FEI_INITIALIZING = 0x00000018,
FEI_LINE_UNAVAILABLE = 0x00000019,
FEI_HANDLED = 0x0000001a,
FEI_FAXSVC_STARTED = 0x0000001b
}
#endregion #region Structs [StructLayout(LayoutKind.Sequential)]
public struct SYSTEMTIME
{
public ushort wYear;
public ushort wMonth;
public ushort wDayOfWeek;
public ushort wDay;
public ushort wHour;
public ushort wMinute;
public ushort wSecond;
public ushort wMilliseconds;
} [StructLayout(LayoutKind.Sequential)]
public struct FAX_DEVICE_STATUS
{
public int SizeOfStruct; // size of this structure
public string CallerId; // caller id string
public string Csid; // station identifier
public int CurrentPage; // current page
public int DeviceId; // permanent line id
public string DeviceName; // device name
public string DocumentName; // document name
public int JobType; // send or receive?
public string PhoneNumber; // sending phone number
public string RoutingString; // routing information
public string SenderName; // sender name
public string RecipientName; // recipient name
public int Size; // size in bytes of the document
public FILETIME StartTime; // starting time of the fax send/receive
public int Status; // current status of the device, see FPS_??? masks
public string StatusString; // status string if the Status field is zero. this may be NULL.
public FILETIME SubmittedTime; // time the document was submitted
public int TotalPages; // total number of pages in this job
public string Tsid; // transmitting station identifier
public string UserName; // user that submitted the active job
} [StructLayout(LayoutKind.Sequential)]
public struct FAX_COVERPAGE_INFO
{
public int SizeOfStruct; // Size of this structure
//
// general
//
public string CoverPageName; // coverpage document name
public bool UseServerCoverPage; // coverpage exists on the fax server
//
// Recipient information
//
public string RecName; //
public string RecFaxNumber; //
public string RecCompany; //
public string RecStreetAddress; //
public string RecCity; //
public string RecState; //
public string RecZip; //
public string RecCountry; //
public string RecTitle; //
public string RecDepartment; //
public string RecOfficeLocation; //
public string RecHomePhone; //
public string RecOfficePhone; //
//
// Sender information
//
public string SdrName; //
public string SdrFaxNumber; //
public string SdrCompany; //
public string SdrAddress; //
public string SdrTitle; //
public string SdrDepartment; //
public string SdrOfficeLocation; //
public string SdrHomePhone; //
public string SdrOfficePhone; //
//
// Misc information
//
public string Note; // public string Subject; //
public SYSTEMTIME TimeSent; // Time the fax was sent
public int PageCount; // Number of pages
} [StructLayout(LayoutKind.Sequential)]
public struct FAX_EVENT
{
public int SizeOfStruct; // Size of this structure
public FILETIME TimeStamp; // Timestamp for when the event was generated
public int DeviceId; // Permanent line id
public int EventId; // Current event id
public int JobId; // Fax Job Id, 0xffffffff indicates inactive job
} [StructLayout(LayoutKind.Sequential, CharSet=CharSet.Unicode)]
public struct FAX_JOB_PARAM
{
public int SizeOfStruct; // size of this structure
public string RecipientNumber; // recipient fax number
public string RecipientName; // recipient name
public string Tsid; // transmitter's id
public string SenderName; // sender name
public string SenderCompany; // sender company
public string SenderDept; // sender department
public string BillingCode; // billing code
public int ScheduleAction; // when to schedule the fax, see JSA defines
public SYSTEMTIME ScheduleTime; // time to send the fax when JSA_SPECIFIC_TIME is used (must be local time)
public int DeliveryReportType; // delivery report type, see DRT defines
public string DeliveryReportAddress; // email address for delivery report (ndr or dr) thru MAPI / SMTP
public string DocumentName; // document name (optional)
public IntPtr CallHandle; // optional call handle //[MarshalAs(UnmanagedType., SizeConst=3)]
public IntPtr[] Reserved; // reserved for ms use only
}
#endregion #region Externs [DllImport("winfax.dll", SetLastError=true)]
public static extern int FaxConnectFaxServer(string MachineName,
[Out] out int FaxHandle); [DllImport("winfax.dll", SetLastError=true)]
public static extern bool FaxInitializeEventQueue(int FaxHandle, int
CompletionPort, int CompletionKey, int hWnd, int MessageStart); [DllImport("winfax.dll", SetLastError=true)]
public static extern void FaxFreeBuffer(IntPtr Buffer); [DllImport("winfax.dll", SetLastError=true)]
public static extern bool FaxClose(int FaxHandle); [DllImport("winfax.dll", SetLastError=true)]
public static extern bool FaxCompleteJobParams([In, Out] ref
FAX_JOB_PARAM JobParams, [In, Out] ref FAX_COVERPAGE_INFO CoverpageInfo); [DllImport("winfax.dll", SetLastError=true)]
public static extern bool FaxSendDocument(int FaxHandle, string FileName, 
[In] ref FAX_JOB_PARAM JobParams, [In] ref FAX_COVERPAGE_INFO CoverpageInfo,
[Out] out int FaxJobId); [DllImport("winfax.dll", SetLastError=true)]
public static extern bool FaxSendDocument(int FaxHandle, string FileName, 
[In] ref FAX_JOB_PARAM JobParams, [In] ref IntPtr CoverpageInfo, 
[Out] out int FaxJobId); [DllImport("winfax.dll", SetLastError=true)]
public static extern bool FaxOpenPort(int FaxHandle, int DeviceId, int Flags, 
[Out] int FaxPortHandle); [DllImport("winfax.dll", SetLastError=true)]
public static extern bool FaxGetDeviceStatus(int FaxPortHandle,
[Out] out FAX_DEVICE_STATUS DeviceStatus); #endregion

Answer 7

public static bool SendFax(string faxDocument, string faxNumber)
{
bool bTerminate = false;
int hCompletionPort = 0;
int completionKey = 0;
int bytesSent = 0;
int hFax = 0;
//IntPtr hFax = new IntPtr(0);
//IntPtr hPort = new IntPtr(0);
int hPort = 0;
int faxJobID = 0;
FAX_DEVICE_STATUS deviceStatus;
FAX_EVENT faxEvent = new FAX_EVENT();
FAX_JOB_PARAM jobParam = new FAX_JOB_PARAM();
FAX_COVERPAGE_INFO coverPageInfo = new FAX_COVERPAGE_INFO(); faxEvent.SizeOfStruct = Marshal.SizeOf(typeof(FAX_EVENT));
IntPtr pFaxEvent = Marshal.AllocHGlobal(faxEvent.SizeOfStruct);
Marshal.StructureToPtr(faxEvent, pFaxEvent, true); jobParam.SizeOfStruct = Marshal.SizeOf(typeof(FAX_JOB_PARAM));
IntPtr pJobParam = Marshal.AllocHGlobal(jobParam.SizeOfStruct);
Marshal.StructureToPtr(jobParam, pJobParam, true); coverPageInfo.SizeOfStruct = Marshal.SizeOf(typeof(FAX_COVERPAGE_INFO));
IntPtr pCoverPageInfo = Marshal.AllocHGlobal(coverPageInfo.SizeOfStruct);
Marshal.StructureToPtr(coverPageInfo, pCoverPageInfo, true); // connect to fax service
if(FaxConnectFaxServer(null, out hFax) == 0)
{
Console.WriteLine("GetLastWin32Error: " + Marshal.GetLastWin32Error().ToString()); //_tprintf( TEXT("FaxConnectFaxServer failed, ec = %d\n"),GetLastError() );
return false;
} // create completion port to poll against while waiting for fax completion
hCompletionPort = Win32.CreateIoCompletionPort(Win32.INVALID_HANDLE_VALUE, 0, 0, 0); if(hCompletionPort == 0)
{
Console.WriteLine("GetLastWin32Error: " + Marshal.GetLastWin32Error().ToString()); //_tprintf( TEXT("CreateIoCompletionPort failed, ec = %d\n"),GetLastError());
FaxClose(hFax);
return false;
} if (!FaxInitializeEventQueue( hFax, hCompletionPort, 0, 0, 0))
{
Console.WriteLine("GetLastWin32Error: " + Marshal.GetLastWin32Error().ToString()); //_tprintf( TEXT("FaxInitializeEventQueue failed, ec = %d\n"),GetLastError() );
FaxClose(hFax);
return false;
} FaxCompleteJobParams(ref jobParam, ref coverPageInfo); jobParam.RecipientNumber = faxNumber;
jobParam.ScheduleAction = (int)FAX_ENUM_JOB_SEND_ATTRIBUTES.JSA_NOW;
jobParam.CallHandle = new IntPtr(0);// IntPtr coverPageNull = new IntPtr(0);
IntPtr coverPageNull = ((IntPtr)((int)(0)));
if(!FaxSendDocument(hFax, faxDocument, ref jobParam, ref coverPageNull, out faxJobID))
{
Console.WriteLine("GetLastWin32Error: " + Marshal.GetLastWin32Error().ToString()); //jobParam = (FAX_JOB_PARAM) Marshal.PtrToStructure(pJobParam,typeof(FAX_JOB_PARAM));
//coverPageInfo = (FAX_COVERPAGE_INFO) Marshal.PtrToStructure(pCoverPageInfo, typeof(FAX_COVERPAGE_INFO)); //_tprintf( TEXT("FaxSendDocument failed, ec = %d \n"),GetLastError() ); FaxClose(hFax);
Win32.CloseHandle(hCompletionPort);
FaxFreeBuffer(pJobParam);
FaxFreeBuffer(pCoverPageInfo);
return false;
} //_tprintf(TEXT("Queued document %s for transmition to %s, JobID = %d\n"), Document, Number, JobId); FaxFreeBuffer(pJobParam);
FaxFreeBuffer(pCoverPageInfo); Marshal.StructureToPtr(faxEvent, pFaxEvent, true); while (!bTerminate &&
(Win32.GetQueuedCompletionStatus(
hCompletionPort,
ref bytesSent,
ref completionKey,
pFaxEvent,
Win32.INFINITE) != 0))
{ faxEvent = (FAX_EVENT) Marshal.PtrToStructure(pFaxEvent,
typeof(FAX_EVENT)); //_tprintf( TEXT("Received event 0x%x\n"),FaxEvent->EventId); switch ((WinFaxEvent) faxEvent.EventId)
{
case WinFaxEvent.FEI_IDLE:
case WinFaxEvent.FEI_COMPLETED:
case WinFaxEvent.FEI_MODEM_POWERED_ON:
case WinFaxEvent.FEI_MODEM_POWERED_OFF:
case WinFaxEvent.FEI_FAXSVC_ENDED:
bTerminate = true;
break; case WinFaxEvent.FEI_JOB_QUEUED:
//_tprintf( TEXT("JobId 0x%x queued\n"),FaxEvent->JobId );
break; case WinFaxEvent.FEI_DIALING:
case WinFaxEvent.FEI_SENDING:
case WinFaxEvent.FEI_RECEIVING:
case WinFaxEvent.FEI_BUSY:
case WinFaxEvent.FEI_NO_ANSWER:
case WinFaxEvent.FEI_BAD_ADDRESS:
case WinFaxEvent.FEI_NO_DIAL_TONE:
case WinFaxEvent.FEI_DISCONNECTED:
case WinFaxEvent.FEI_FATAL_ERROR:
if (FaxOpenPort(hFax, faxEvent.DeviceId, (int) FAX_PORT_OPEN_TYPE.PORT_OPEN_QUERY, hPort) )
{
if (FaxGetDeviceStatus(hPort, out deviceStatus) )
{
IntPtr pDeviceStatus = new IntPtr();
deviceStatus.SizeOfStruct = Marshal.SizeOf(typeof(FAX_DEVICE_STATUS));
Marshal.StructureToPtr(deviceStatus, pDeviceStatus, true); //PrintDeviceStatus(deviceStatus);
FaxFreeBuffer(pDeviceStatus);
}
FaxClose(hPort);
}
break;
}
} FaxClose(hFax);
Win32.CloseHandle(hCompletionPort);
return true;
}}

Answer 8

你把所有用struct定义的数据类型，改成用class定义，然后用
//If you use FAX_JOB_PARAM and FAX_COVERPAGE_INFO as a CLASS !
[DllImport("winfax.dll", SetLastError = true)]
[DllImport(DLLWinFax, SetLastError = true)]
static extern bool FaxSendDocument(IntPtr FaxHandle, string FileName,
FAX_JOB_PARAM JobParams, FAX_COVERPAGE_INFO CoverpageInfo,
out uint FaxJobId);那么给一个空的对象，可以用null来试。