一)在utils.h和utils.c中完成16进制字符'0'-'9','A'-'F','a'-'f'与十六进制数据0-15的转换功能
utils.h
#ifndef _UTIL_H_ #define _UTIL_H_ //char Hex2Char(int i); //int Char2Hex(char c); int Hex2Char(int fromi,char * toc); int Char2Hex(char fromc,int * toi); int Bitstr2ByteArr(char * bs,char * ba); int ByteArr2Bitstr(char * ba,char * bs); int Int2ByteArr(int i,char * ba); int ByteArr2Int(char * ba,int * i); #endif
utils.c
#include<stdio.h> #include"util.h" char Hstr = {'0','1','2','3','4','5','6','7','8','9','A','B','C','D','E','F'}; char Hex2Char(int i){ if(i >= 0 && i <= 9){ return i + 0x30; // return i + '0' } if(i >= 10 && i <= 15){ return i + 0x37; // return i + 'A' - 10 } return 0; } /* int Hex2Char(int fromi,char *toc) { if(fromi>=0&&fromi<=9) { *toc= fromi+'0'; } else if(fromi>=10&&fromi<=15) { *toc = fromi+'A'-10; } else { printf("error"); } return 0; } int Char2Hex(char fromc,int *toi) { if(fromc>='0'&& fromc<='9') { *toi= fromc-'0'; } else if(fromc>='A'&& fromc<='F') { *toi= fromc-'A'+10; } else { printf("error"); } return 0; } */
main.c
#include"utils.h" int main(){ int n1,n2; char c1,c2; printf("请输入一个0~15的数:"); scanf("%d",&n1); Hex2Char(n1,&c1); printf("对应的16进制字符是%c\n",c1); printf("请输入一个16进制字符:");
scanf("%c",&c2); Char2Hex(c2,&n2); printf("%c对应的数是%d\n",c2,n2); }