LPOVERLAPPED_COMPLETION_ROUTINE與功能

我希望異步數據寫入使用WriteFileEx從WINAPI到文件不兼容，但我有回調的一個問題。LPOVERLAPPED_COMPLETION_ROUTINE與功能

我得到如下錯誤： 類型的參數「無效（*）（DWORD dwErrorCode，DWORD dwNumberOfBytesTransfered，LPOVERLAPPED lpOverlapped的）」與類型「LPOVERLAPPED_COMPLETION_ROUTINE」的參數不兼容

什麼我做錯了嗎？

這裏是代碼：

// Callback 
void onWriteComplete(
     DWORD dwErrorCode, 
     DWORD dwNumberOfBytesTransfered, 
     LPOVERLAPPED lpOverlapped) { 
    return; 
} 

BOOL writeToOutputFile(String ^outFileName, List<String ^> ^fileNames) { 
    HANDLE hFile; 
    char DataBuffer[] = "This is some test data to write to the file."; 
    DWORD dwBytesToWrite = (DWORD) strlen(DataBuffer); 
    DWORD dwBytesWritten = 0; 
    BOOL bErrorFlag = FALSE; 

    pin_ptr<const wchar_t> wFileName = PtrToStringChars(outFileName); 

    hFile = CreateFile(
     wFileName,    // name of the write 
     GENERIC_WRITE,   // open for writing 
     0,      // do not share 
     NULL,     // default security 
     CREATE_NEW,    // create new file only 
     FILE_FLAG_OVERLAPPED, 
     NULL);     // no attr. template 

    if (hFile == INVALID_HANDLE_VALUE) { 
     return FALSE; 
    } 

    OVERLAPPED oOverlap; 
    bErrorFlag = WriteFileEx(
     hFile,   // open file handle 
     DataBuffer,  // start of data to write 
     dwBytesToWrite, // number of bytes to write 
     &oOverlap,  // overlapped structure 
     onWriteComplete), 

    CloseHandle(hFile); 
}

來源

2015-01-06 Mike_Device

你應該仔細閱讀documentation開始。這部分是特別重要的：

The OVERLAPPED data structure must remain valid for the duration of the write operation. It should not be a variable that can go out of scope while the write operation is pending completion.

你沒有達到那個要求，你需要緊急解決這個問題。

至於編譯器錯誤，這很簡單。您的回撥不符合要求。再次諮詢documentation其中它的簽名是給出如下：

VOID CALLBACK FileIOCompletionRoutine(
    _In_  DWORD dwErrorCode, 
    _In_  DWORD dwNumberOfBytesTransfered, 
    _Inout_ LPOVERLAPPED lpOverlapped 
);

您省略CALLBACK指定調用約定。

來源

2015-01-06 23:00:39

謝謝！現在，它的工作 –

順便說一句，你能再次幫助我嗎？回調在這裏根本不叫。我在等，但沒有任何事發生 –

您需要閱讀文檔。你沒有檢查返回值。或者調用GetLastError。 –

LPOVERLAPPED_COMPLETION_ROUTINE與功能

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