当判断整数时
- 示例: 判断整数范围
#include <stdio.h> int main() { unsigned char buf[6]={0x00,0x07,0x11,0x60,0x61,0x66}; for(int i=0;i<6;i++) switch(buf[i]) { case 0x00 ... 0x10: printf("buf[%d] is 0x0 ~0x10\n",i); break; case 0x11 ... 0x20: printf("buf[%d] is 0x11~0x20\n",i); break; case 0x30 ... 0x60: printf("buf[%d] is 0x30~0x60\n",i); break; case 0x61 ... 0xff: printf("buf[%d] is 0x61~0xff\n",i); break; } }
打印:
当判断字符时
- 示例: 将"0x00"~"0xff"转化为数值0x00~0xff
#include <stdio.h> int main() { char buf[6][6]={"0xff","0X02","0X1f","0xf1","0xa1","0Xb0"};
for(int i=0;i<6;i++) if(buf[i][0]=='0'&&(buf[i][1]=='x' || buf[i][1]=='X')) //匹配前缀 { unsigned char val=0; int err=0; for(int j=2;j<4;j++) switch(buf[i][j]) { case '0' ... '9' : val= val*16 + (buf[i][j]-'0'); break; case 'a' ... 'f' : val= val*16 + (buf[i][j]-'a'+10); break; case 'A' ... 'F' : val= val*16 + (buf[i][j]-'A'+10); break; default : err =1; break; }
if(!err) printf("buf[%d] = 0X%02X\n",i,val); else printf("buf[%d] ERR \n",i); } else printf("buf[%d] ERR \n",i); }
打印:
