C# 有没有比 FileInfo.Length 更快的方法来比较多个文件？

Question

I have been trying to compare files from two differents environments. Both environment are accessed via a network drive.

First, I checked if the file is present in both environments (to save time), then I ask for a FileInfo on both files to compare their filesizes (FileInfo.Length).

My goal is to populate a listview with every files that does not have the same size to investigate on these later.

I find it hard to understand that windows explorer gets the filesize of a lot of files so quickly and that FileInfo is taking so long...

Thanks. Ben

Answer 1

If you use DirectoryInfo.GetFiles( some-search-pattern ) to get the files, then use the FileInfo-instance returned from that call, then the property FileInfo.Length will be cached from the search.

Whether this will be of any help obviously depends on how the search performs in comparison to the check you are currently doing (if the search is slower, you may not gain anything). Still, it may be worth looking into.

Answer 2

You can try doing it the operating system way. You call via win32 system calls. You can start with this page,

http://www.pinvoke.net/default.aspx/kernel32.getfilesize