C语言文件读写，文件相关操作

C语言文件读写，文件相关操作

1.C语言万物皆是地址，文件读操作

//
// Created by MagicBook on 2023-10-22.
//
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>int main() {//文件路径，r,w,rb,rw//返回值结构体char *fileName = "C:\\Users\\MagicBook\\Desktop\\tv.txt";//读的权限，文件必须存在FILE *file = fopen(fileName, "r");if (!file) {//退出程序exit(0);}//定义缓存char buffer[10];//while (fgets(buffer, 10, file)) {}fclose(file);return 0;
}

2.文件的写

//
// Created by MagicBook on 2023-10-22.
//
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>int main() {//文件路径，r,w,rb,rw//返回值结构体char *fileName = "C:\\Users\\MagicBook\\Desktop\\tvv.txt";//写的权限，会自动生成文件FILE *file = fopen(fileName, "w");if (!file) {//退出程序exit(0);}fputs("sdsadds", file);fclose(file);return 0;
}

3.文件的复制

//
// Created by MagicBook on 2023-10-22.
//
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>//二进制文件来操作rb，rw，
int main() {//文件路径，r,w,rb,rw//返回值结构体char *fileName = "C:\\Users\\MagicBook\\Desktop\\tv.txt";//目标char *fileNameCopy = "C:\\Users\\MagicBook\\Desktop\\tvv.txt";//读取二进制数据FILE *file1 = fopen(fileName, "rb");//写入二进制数据FILE *file2 = fopen(fileName, "rw");if (!file1 || !file2) {exit(0);}//412 * 4int buffer[512];//每次接收的长度int len;//容器buffer,每次偏移多少，容器大小，while ((len = fread(buffer, sizeof(int), sizeof(buffer) / sizeof(int), file1) != 0)) {fwrite(buffer, sizeof(int), len, fileNameCopy);}fclose(file1);fclose(file2);return 0;
}

4.获取文件的大小

//
// Created by MagicBook on 2023-10-22.
//
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>//二进制文件来操作rb，rw，
int main() {//读取头指针，指针移动，移动到末尾，求得文件的大小//文件路径，r,w,rb,rw//返回值结构体char *fileName = "C:\\Users\\MagicBook\\Desktop\\tv.txt";//读取二进制数据FILE *file1 = fopen(fileName, "rb");//写入二进制数据FILE *file2 = fopen(fileName, "rw");if (!file1 || !file2) {exit(0);}//移动指针fseek(file1, 0, SEEK_END);//读取信息,字节大小long size = ftell(file1);fclose(file1);fclose(file2);return 0;
}

5.文件的加密解密

加密

//
// Created by MagicBook on 2023-10-22.
//
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>//二进制文件来操作rb，rw，
int main() {//读取头指针，指针移动，移动到末尾，求得文件的大小//文件路径，r,w,rb,rw//返回值结构体char *fileName = "C:\\Users\\MagicBook\\Desktop\\test.png";//加密char *fileNameEncode = "C:\\Users\\MagicBook\\Desktop\\test_encode.png";//读取二进制数据FILE *file1 = fopen(fileName, "rb");//写入二进制数据FILE *file2 = fopen(fileNameEncode, "rw");if (!file1 || !file2) {exit(0);}//加密：破坏二进制文件//解密：还原文件//接收读取的值int c;//返回值EOFwhile ((c == fgetc(file1) != EOF)) {fputc(c^5,file2);}fclose(file1);fclose(file2);return 0;
}

解密

//
// Created by MagicBook on 2023-10-22.
//
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>//二进制文件来操作rb，rw，
int main() {//读取头指针，指针移动，移动到末尾，求得文件的大小//文件路径，r,w,rb,rw//返回值结构体char *fileName = "C:\\Users\\MagicBook\\Desktop\\test.png";//加密char *fileNameEncode = "C:\\Users\\MagicBook\\Desktop\\test_encode.png";//密钥char *password = "123456";//读取二进制数据FILE *file1 = fopen(fileName, "rb");//写入二进制数据FILE *file2 = fopen(fileNameEncode, "rw");if (!file1 || !file2) {exit(0);}//加密：破坏二进制文件//解密：还原文件//接收读取的值int c;int index = 0;int len = strlen(password);//返回值EOFwhile ((c == fgetc(file1)) != EOF) {char item = password[index % len];fputc(c ^ item, file2);index++;}fclose(file1);fclose(file2);return 0;
}