如何查找下一个用户定义的日间时间

• 下载源代码和示例 - 6.29 KB

引言

本文将指导您完成一个简单的算法，以查找下周的特定日期。

例如，您想找到下个星期日
今天的日期：2009/11/27
程序将返回：2009/11/29 (或相应的UNIX时间戳)

Using the Code

好的，您可以通过调用该函数来使用该算法函数

struct tm * nextday (int day=0)

此函数将返回一个struct tm *变量类型，其中包含有关您选择的day 的所有信息。要了解更多关于tm struct的信息，请点击这里。

time_t nextday_UNIX (int day=0) 

此函数将返回一个time_t 变量类型，其中仅包含UNIX时间戳格式。要了解更多关于time_t的信息，请点击这里。

在两个函数中，您必须输入一个参数（默认值为0）。此参数是星期几的数字，从星期日开始，因此

星期日 -> 0
星期一 -> 1
星期二 -> 2
[...]
星期六 -> 6

如果您尝试传递不在此范围内的值，则两个函数都将返回NULL。

好的，停止谈论，这是第一个函数，代码中自解释

/*
=================================
HOW TO FIND NEXT DAY TIME (struct)
=================================
by ItalianSoul

The function returns a struct type tm.
To extract real date you can use the following codes:
         
punt->tm_mday //Day
punt->tm_mon+1 //Month
punt->tm_year+1900 //Year

*/
struct tm * nextday (int day=0)
{
       /* Initialize variables */
  time_t rawtime; 
  struct tm * timeinfo;

      /* get current timeinfo*/
  time ( &rawtime );
  timeinfo = localtime ( &rawtime );
  
     /* call mktime: timeinfo->tm_wday will be set */
   mktime ( timeinfo );
      
/*Now let's find next day time*/
/*Initialize temporarily variables */
time_t nextday;
struct tm* nextdaydate;

/*Now I'll search which day is it and I'll add 86400 seconds(a day) *days remaining */
if(timeinfo->tm_wday == day)
      nextday = rawtime + (86400*7);
else if (timeinfo->tm_wday == day-6)
     nextday = rawtime + (86400*6);
else if (timeinfo->tm_wday == day-5)
     nextday = rawtime + (86400*5);
else if (timeinfo->tm_wday == day-4)
     nextday = rawtime + (86400*4);
else if (timeinfo->tm_wday == day-3)
     nextday = rawtime + (86400*3);
else if (timeinfo->tm_wday == day-2)
     nextday = rawtime + (86400*2);
else if (timeinfo->tm_wday == day-1)
     nextday = rawtime + (86400);
else
    return NULL;

/*Convert him to localtime*/
nextdaydate = localtime(&nextday);
return nextdaydate; //Return struct
}

这是另一个（UNIX时间戳）

 /*
=================================
HOW TO FIND NEXT DAY TIME (UNIX)
=================================
by ItalianSoul

The function returns an time_t format variable, 
that contains UNIX date format of next Sunday (or day that you selected)
*/

time_t nextday_UNIX (int day=0)
{
       /* Initialize variables */
  time_t rawtime; 
  struct tm * timeinfo;

      /* get current timeinfo*/
  time ( &rawtime );
  timeinfo = localtime ( &rawtime );
  
     /* call mktime: timeinfo->tm_wday will be set */
   mktime ( timeinfo );
      
/*Now let's find next day time*/
/*Intialize temporarily variables */
time_t nextday;

/*Now I'll search which day is it and I'll add 86400 seconds(a day) *days remaining */
if(timeinfo->tm_wday == day)
     nextday = rawtime + (86400*7);
else if (timeinfo->tm_wday == day-6)
     nextday = rawtime + (86400*6);
else if (timeinfo->tm_wday == day-5)
     nextday = rawtime + (86400*5);
else if (timeinfo->tm_wday == day-4)
     nextday = rawtime + (86400*4);
else if (timeinfo->tm_wday == day-3)
     nextday = rawtime + (86400*3);
else if (timeinfo->tm_wday == day-2)
     nextday = rawtime + (86400*2);
else if (timeinfo->tm_wday == day-1)
     nextday = rawtime + (86400);
else
    return (time_t) NULL;

  return  nextday; //Return the result as time_t
}

示例

好的，伙计们，这是一个查找下个星期日的示例

#include <stdio.h>
#include <time.h>  //You must include time.h library to compile that functions
int main()
{
   time_t sunday_unix;
   struct tm *sunday_date;
    sunday_date=nextday(0);
    sunday_unix=nextday_UNIX(7);
    if(sunday_date != NULL)
    {
    printf("Next sunday will come on: %d\\%d\\%d",
	sunday_date->tm_mday,sunday_date->tm_mon+1,sunday_date->tm_year+1900);
    }
    if(sunday_unix != (time_t)NULL)
    {
    printf("\nNext sunday will come on: %d",sunday_unix);
    }
}

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历史

• 1.0 - 2009/11/29：初始发布