如何在磁盘中获取文件大小?

How do I get the size of file in disk? as show in the Windows explorer? e.g, a filename has:

如何在磁盘中获取文件的大小?如Windows资源管理器所示?e。g,文件名:

size: 172 bytes (172 bytes)
size on disk: 0 bytes

But my application shows:

但是我的应用程序显示:

GetDiskFreeSpace(L"C:\\" &sectorsPerCluster, &lpBytesPerSector,
            &numberOfFreeClusters, &totalNumberOfClusters));
    int TotalSize = lpBytesPerSector * ((fileLength + lpBytesPerSector - 1) / lpBytesPerSector);
    printf("fileLength = %d\n", fileLength);
    printf("TotalSize = %d\n", TotalSize);

it output:

输出:

fileLength = 172
TotalSize = 512

What am I missing to compute properly the size in disk of the filename?

要正确计算文件名在磁盘中的大小，我缺少什么?

2 个解决方案

#1

MSDN:

https://docs.microsoft.com/en-us/windows/desktop/api/fileapi/nf-fileapi-getfilesize

Some psuedo code:

推出一些伪代码:

HANDLE hFile = INVALID_HANDLE_VALUE; // call CreateFileA/W and Open the file
DWORD dwSize = 0;
GetFileSize(hFile, &dwSize); // check result of the call... if it failed call CloseHandle.
printf("GetFileSize() got: %d bytes");

Or if this does not work for you, You can always call NtQueryInformationFile and passing FileStandardInformation to FileInformationClass.

或者如果这对您不起作用，您可以调用NtQueryInformationFile并将FileStandardInformation传递给FileInformationClass。

#2

-2

You can try below code.

你可以试试下面的代码。

long filesize;
char *filename = "xyz.txt";
FILE *fp = fopen(filename, "r");
if(fp)
{
    fseek(fp, 0L, SEEK_END);
    filesize = ftell(fp);
    fseek(fp, 0L, SEEK_SET);
    printf("File size = %ld", filesize);
}

#1