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有人可以给我一些工作示例，说明如何从 C++ API 创建、添加消息、读取和销毁私有消息队列吗？我尝试了 MSDN 的代码片段，但我无法让它们正常工作。

谢谢

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2 回答 2

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实际上这是我感兴趣的代码：

#include "windows.h"
#include "mq.h"
#include "tchar.h"


HRESULT CreateMSMQQueue(
                        LPWSTR wszPathName, 
                        PSECURITY_DESCRIPTOR pSecurityDescriptor,
                        LPWSTR wszOutFormatName,
                        DWORD *pdwOutFormatNameLength
                        )
{

  // Define the maximum number of queue properties.
  const int NUMBEROFPROPERTIES = 2;


  // Define a queue property structure and the structures needed to initialize it.
  MQQUEUEPROPS   QueueProps;
  MQPROPVARIANT  aQueuePropVar[NUMBEROFPROPERTIES];
  QUEUEPROPID    aQueuePropId[NUMBEROFPROPERTIES];
  HRESULT        aQueueStatus[NUMBEROFPROPERTIES];
  HRESULT        hr = MQ_OK;


  // Validate the input parameters.
  if (wszPathName == NULL || wszOutFormatName == NULL || pdwOutFormatNameLength == NULL)
  {
    return MQ_ERROR_INVALID_PARAMETER;
  }



  DWORD cPropId = 0;
  aQueuePropId[cPropId] = PROPID_Q_PATHNAME;
  aQueuePropVar[cPropId].vt = VT_LPWSTR;
  aQueuePropVar[cPropId].pwszVal = wszPathName;
  cPropId++;

  WCHAR wszLabel[MQ_MAX_Q_LABEL_LEN] = L"Test Queue";
  aQueuePropId[cPropId] = PROPID_Q_LABEL;
  aQueuePropVar[cPropId].vt = VT_LPWSTR;
  aQueuePropVar[cPropId].pwszVal = wszLabel;
  cPropId++;



  QueueProps.cProp = cPropId;               // Number of properties
  QueueProps.aPropID = aQueuePropId;        // IDs of the queue properties
  QueueProps.aPropVar = aQueuePropVar;      // Values of the queue properties
  QueueProps.aStatus = aQueueStatus;        // Pointer to the return status



  WCHAR wszFormatNameBuffer[256];
  DWORD dwFormatNameBufferLength = sizeof(wszFormatNameBuffer)/sizeof(wszFormatNameBuffer[0]);
  hr = MQCreateQueue(pSecurityDescriptor,         // Security descriptor
                     &QueueProps,                 // Address of queue property structure
                     wszFormatNameBuffer,         // Pointer to format name buffer
                     &dwFormatNameBufferLength);  // Pointer to receive the queue's format name length



  if (hr == MQ_OK || hr == MQ_INFORMATION_PROPERTY)
  {
    if (*pdwOutFormatNameLength >= dwFormatNameBufferLength)
    {
      wcsncpy_s(wszOutFormatName, *pdwOutFormatNameLength - 1, wszFormatNameBuffer, _TRUNCATE);

      wszOutFormatName[*pdwOutFormatNameLength - 1] = L'\0';
      *pdwOutFormatNameLength = dwFormatNameBufferLength;
    }
    else
    {
      wprintf(L"The queue was created, but its format name cannot be returned.\n");
    }
  }
  return hr;
}

这大概会创建一个队列......但是有一些部分缺少这个工作，这就是为什么我需要一个简单的例子。

于 2008-09-23T11:53:19.130 回答
-1

不太确定您将如何创建或销毁消息队列。Windows 应该为每个线程创建一个。

如果您使用 MFC，则任何 CWinThread 和 CWnd 派生类都有一个易于访问的消息队列（使用 PostMessage 或 PostThreadMessage 和 ON_COMMAND 宏）。要使用 Windows API 执行类似的操作，我认为您需要编写自己的消息泵，例如 CWinApp 的 run 方法。

MSG msg;
BOOL bRet; 
while( (bRet = GetMessage( &msg, NULL, 0, 0 )) != 0)
{ 
    if (bRet == -1)
    {
        // handle the error and possibly exit
    }
    else
    {
        TranslateMessage(&msg); 
        DispatchMessage(&msg); 
    }
}

...是 MSDN 文档中的示例。这是你用的吗？什么不起作用？

于 2008-09-23T11:35:53.400 回答