每个C/C++程序员都应该知道的四种文件处理技巧-yiteyi-C++库

我们将讨论下面列出的四种文件黑客-

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重命名–使用C/C重命名文件++
删除–使用C/C删除文件++
文件大小–使用C/C获取文件大小++
检查是否存在–检查C/C中是否存在文件++

                     // A C++ Program to demonstrate the                   
                     // four file hacks every C/C++ must know                   
                             
                     // Note that we are assuming that the files                   
                     // are present in the same file as the program                   
                     // before doing the below four hacks                   
                     #include<stdio.h>                   
                     #include<stdlib.h>                   
                     #include<stdbool.h>                   
                             
                     // A Function to get the file size                   
                     unsigned                               long                               long                               int                               fileSize(                               const                               char                               *filename)                   
                     {                   
                                         // Open the file                   
                                         FILE                               *fh =                               fopen                               (filename,                               "rb"                               );                   
                                         fseek                               (fh, 0, SEEK_END);                   
                                         unsigned                               long                               long                               int                               size =                               ftell                               (fh);                   
                                         fclose                               (fh);                   
                             
                                         return                               (size);                   
                     }                   
                             
                     // A Function to check if the file exists or not                   
                     bool                               fileExists(                               const                               char                               * fname)                   
                     {                   
                                         FILE                               *file;                   
                                         if                               (file =                               fopen                               (fname,                               "r"                               ))                   
                                         {                   
                                         fclose                               (file);                   
                                         return                               (                               true                               );                   
                                         }                   
                                         return                               (                               false                               );                   
                     }                   
                             
                     // Driver Program to test above functions                   
                     int                               main()                   
                     {                   
                                         printf                               (                               "%llu Bytes"                               , fileSize(                               "Passwords.txt"                               ));                   
                                         printf                               (                               "%llu Bytes"                               , fileSize(                               "Notes.docx"                               ));                   
                             
                                         if                               (fileExists(                               "OldData.txt"                               ) ==                               true                               )                   
                                         printf                               (                               "The File exists"                               );                   
                                         else                   
                                         printf                               (                               "The File doen't exist"                               );                   
                             
                                         rename                               (                               "Videos"                               ,                               "English_Videos"                               );                   
                                         rename                               (                               "Songs"                               ,                               "English_Songs"                               );                   
                             
                                         remove                               (                               "OldData.txt"                               );                   
                                         remove                               (                               "Notes.docx"                               );                   
                             
                                         if                               (fileExists(                               "OldData.txt"                               ) ==                               true                               )                   
                                         printf                               (                               "The File exists"                               );                   
                                         else                   
                                         printf                               (                               "The File doesn't exist"                               );                   
                             
                                         return                               0;                   
                     }                   