我想获得系统的当前时间。为此,我在C中使用以下代码:
time_t now;
struct tm *mytime = localtime(&now);
if ( strftime(buffer, sizeof buffer, "%X", mytime) )
{
printf("time1 = \"%s\"\n", buffer);
}
问题是这段代码给出了一些随机时间。此外,随机时间每次都不同。我想要系统的当前时间。
答案 0 :(得分:109)
从here复制粘贴:
/* localtime example */
#include <stdio.h>
#include <time.h>
int main ()
{
time_t rawtime;
struct tm * timeinfo;
time ( &rawtime );
timeinfo = localtime ( &rawtime );
printf ( "Current local time and date: %s", asctime (timeinfo) );
return 0;
}
(只需将“void”添加到main()参数列表中,以使其在C)
中起作用答案 1 :(得分:62)
初始化您的now
变量。
time_t now = time(0); // Get the system time
localtime
函数用于将传递的time_t
中的时间值转换为struct tm
,它实际上并不检索系统时间。
答案 2 :(得分:32)
简单方法:
#include <time.h>
#include <stdio.h>
int main(void)
{
time_t mytime = time(NULL);
char * time_str = ctime(&mytime);
time_str[strlen(time_str)-1] = '\0';
printf("Current Time : %s\n", time_str);
return 0;
}
答案 3 :(得分:10)
为了扩展上面@mingos的答案,我编写了以下函数来将我的时间格式化为特定格式([dd mm yyyy hh:mm:ss])。
// Store the formatted string of time in the output
void format_time(char *output){
time_t rawtime;
struct tm * timeinfo;
time ( &rawtime );
timeinfo = localtime ( &rawtime );
sprintf(output, "[%d %d %d %d:%d:%d]",timeinfo->tm_mday, timeinfo->tm_mon + 1, timeinfo->tm_year + 1900, timeinfo->tm_hour, timeinfo->tm_min, timeinfo->tm_sec);
}
可以找到有关struct tm
的更多信息here。
答案 4 :(得分:8)
#include<stdio.h>
#include<time.h>
void main()
{
time_t t;
time(&t);
printf("\n current time is : %s",ctime(&t));
}
答案 5 :(得分:6)
你可以使用这个功能来获取当前的当地时间。如果你想要gmtime然后使用gmtime函数而不是localtime。欢呼声
time_t my_time;
struct tm * timeinfo;
time (&my_time);
timeinfo = localtime (&my_time);
CCLog("year->%d",timeinfo->tm_year+1900);
CCLog("month->%d",timeinfo->tm_mon+1);
CCLog("date->%d",timeinfo->tm_mday);
CCLog("hour->%d",timeinfo->tm_hour);
CCLog("minutes->%d",timeinfo->tm_min);
CCLog("seconds->%d",timeinfo->tm_sec);
答案 6 :(得分:2)
如果您只需要没有日期的时间。
MyClassWithProperties obj;
auto firstObject = std::make_shared<QObject>();
auto secondObject = std::make_shared<QObject>();
QVariantList values = { QVariant::fromValue(firstObject), QVariant::fromValue(secondObject) };
obj.setProperty("addressTableModel", values)
答案 7 :(得分:1)
#include <stdio.h>
#include <time.h>
void main()
{
time_t t;
time(&t);
clrscr();
printf("Today's date and time : %s",ctime(&t));
getch();
}
答案 8 :(得分:0)
src:https://en.wikipedia.org/wiki/C_date_and_time_functions
#include <time.h>
#include <stdlib.h>
#include <stdio.h>
int main(void)
{
time_t current_time;
char* c_time_string;
/* Obtain current time. */
current_time = time(NULL);
if (current_time == ((time_t)-1))
{
(void) fprintf(stderr, "Failure to obtain the current time.\n");
exit(EXIT_FAILURE);
}
/* Convert to local time format. */
c_time_string = ctime(¤t_time);
if (c_time_string == NULL)
{
(void) fprintf(stderr, "Failure to convert the current time.\n");
exit(EXIT_FAILURE);
}
/* Print to stdout. ctime() has already added a terminating newline character. */
(void) printf("Current time is %s", c_time_string);
exit(EXIT_SUCCESS);
}
输出为:
Current time is Thu Sep 15 21:18:23 2016
答案 9 :(得分:0)
建议使用 localtime_s
而不是 localtime
。
这应该有效。
time_t current_raw_time = time(0); // System time: number of seconds since 00:00, Jan 1 1970 UTC
struct tm day_time;
localtime_s(&day_time, ¤t_raw_time);
day_time
将具有以下成员:
struct tm
{
int tm_sec; // seconds after the minute - [0, 60] including leap second
int tm_min; // minutes after the hour - [0, 59]
int tm_hour; // hours since midnight - [0, 23]
int tm_mday; // day of the month - [1, 31]
int tm_mon; // months since January - [0, 11]
int tm_year; // years since 1900
int tm_wday; // days since Sunday - [0, 6]
int tm_yday; // days since January 1 - [0, 365]
int tm_isdst; // daylight savings time flag
};
请注意,localtime
不提供毫秒。
答案 10 :(得分:-5)
伙计们,我有了一种获得系统时间的新方法。虽然它冗长而且充满了愚蠢的作品,但通过这种方式你可以获得整数格式的系统时间。
#include <stdio.h>
#include <stdlib.h>
int main()
{
FILE *fp;
char hc1,hc2,mc1,mc2;
int hi1,hi2,mi1,mi2,hour,minute;
system("echo %time% >time.txt");
fp=fopen("time.txt","r");
if(fp==NULL)
exit(1) ;
hc1=fgetc(fp);
hc2=fgetc(fp);
fgetc(fp);
mc1=fgetc(fp);
mc2=fgetc(fp);
fclose(fp);
remove("time.txt");
hi1=hc1;
hi2=hc2;
mi1=mc1;
mi2=mc2;
hi1-=48;
hi2-=48;
mi1-=48;
mi2-=48;
hour=hi1*10+hi2;
minute=mi1*10+mi2;
printf("Current time is %d:%d\n",hour,minute);
return 0;
}