如何使用C將二進制字符串轉換為十六進制？

Question

如何使用C將8位二進制字符串（例如“ 10010011”）轉換為十六進制？

Answer 1

#include <stdlib.h>

strtol("10010011", NULL, 2);

Answer 2

像這樣：

char *bin="10010011";
char *a = bin;
int num = 0;
do {
    int b = *a=='1'?1:0;
    num = (num<<1)|b;
    a++;
} while (*a);
printf("%X\n", num);

Answer 3

void binaryToHex(const char *inStr, char *outStr) {
    // outStr must be at least strlen(inStr)/4 + 1 bytes.
    static char hex[] = "0123456789ABCDEF";
    int len = strlen(inStr) / 4;
    int i = strlen(inStr) % 4;
    char current = 0;
    if(i) { // handle not multiple of 4
        while(i--) {
            current = (current << 1) + (*inStr - '0');
            inStr++;
        }
        *outStr = hex[current];
        ++outStr;
    }
    while(len--) {
        current = 0;
        for(i = 0; i < 4; ++i) {
            current = (current << 1) + (*inStr - '0');
            inStr++;
        }
        *outStr = hex[current];
        ++outStr;
    }
    *outStr = 0; // null byte
}

Answer 4

怎么樣

char *binary_str = "10010011";
unsigned char hex_num = 0;

for (int i = 0, char *p = binary_str; *p != '\0'; ++p, ++i)
{
    if (*p == '1' )
    {
        hex_num |= (1 << i);
    }
}

現在您有了hex_num，就可以使用它來做您想做的事情。 請注意，您可能要驗證輸入字符串的長度或將循環限制為hex_num中的位數。