检查当前时间(不带日期)是否在 C 中的两个时间之间

Question

你能帮我用 C 实现这个吗:

 ((on_time <= off_time and CURTIME() >= on_time and CURTIME() <= off_time) or
 (off_time < on_time and (CURTIME() <= off_time or CURTIME() >= on_time))

我有 on_time = 18:00:00 和 off_time = 01:00:00(第二天午夜后)。我想检查当前时间:19:27:00是否在 on 和 off_time 之间。 on 和 off_time 是字符串。

谢谢

Answer 1

最短的比较解决方案是将所有字符串时间戳转换为 time_t 值。

Improving the source as Brian McFarland suggests memset().

struct tm tmVar;
time_t t_on_time, t_off_time, t_curr_time;

    memset(&tmVar, 0, sizeof(tmVar));    
    if(sscanf(on_time, "%d:%d:%d", &tmVar.tm_hour,  &tmVar.tm_min,  &tmVar.tm_sec)==3) {
        t_on_time = mktime(&tmVar);
    }
    memset(&tmVar, 0, sizeof(tmVar)); 
    if(sscanf(off_time, "%d:%d:%d", &tmVar.tm_hour,  &tmVar.tm_min,  &tmVar.tm_sec)==3) {
        t_off_time = mktime(&tmVar);
    }
    memset(&tmVar, 0, sizeof(tmVar)); 
    if(sscanf(CURTIME(), "%d:%d:%d", &tmVar.tm_hour,  &tmVar.tm_min,  &tmVar.tm_sec)==3) {
        t_curr_time = mktime(&tmVar);
    }

你的比较是:

if (((t_on_time <= t_off_time) && (t_curr_time >= t_on_time) && (t_curr_time <= t_off_time)) ||
 ((t_off_time < t_on_time) && ((t_curr_time <= t_off_time) || (t_curr_time >= t_on_time))) {
    // To do something
}