将 4 个字符组合成一个 unsigned long

Question

我只想将 4 个字符组合成一个 unsigned long 变量，如下所示。

char y[16];
unsigned long Timer ;

y[12] = '1' ;
y[13] = '0' ;
y[14] = '1' ;
y[15] = '1' ; 
Timer  =   y[15] - '0' ;
Timer |=  (unsigned long) (y[12] - '0' << 24);
Timer |=  (unsigned long) (y[13] - '0'  << 16);
Timer |=  (unsigned long) (y[14] - '0'  << 8);

printf("%lu" , Timer);

我希望计时器等于 1011 但我一直得到 1 作为输出。

Answer 1

这应该适合你:

(你只需要知道技巧)

#include <stdio.h>

int main() {

    char y[16];
    unsigned long Timer ;

    y[12] = '1';
    y[13] = '0';
    y[14] = '1';
    y[15] = '1';

    Timer = y[12] - '0';  //- '0' To get the digit, here 1, and this for every digit
    Timer = (Timer * 10) + y[13] - '0';  //*10 to make place for the next digit, and this for every digit (expect the 1st one)
    Timer = (Timer * 10) + y[14] - '0';
    Timer = (Timer * 10) + y[15] - '0';

    printf("%lu" , Timer);

    return 0;

}

输出:

1011