How to use sumif function Detailed explanation of how to use strtotime function in PHP

There is a function called strtotime in PHP. strtotime implementation function: get the timestamp of a certain date, or get the timestamp of a certain time. strtotime parses the date and time description of any English text into a Unix timestamp [converts the system time into a unix timestamp]
1. Get the unix timestamp of the specified date
strtotime("2009-1-22") The example is as follows:
1 .echo strtotime("2009-1-22")
Result: 1232553600
Description: Return the timestamp of 0:00:00 on January 22, 2009
Second, get the English text date and time
The example is as follows:
Easy to compare, Use date to convert the current timestamp and the specified timestamp into system time
(1) Print the timestamp at this time tomorrow strtotime("+1 day")
Current time:
1.echo date("Y-m-d H:i:s ",time())
Result: 2009-01-22 09:40:25
Specified time:
1.echo date("Y-m-d H:i:s",strtotime("+1 day"))
Result: 2009-01-23 09:40:25
(2) Print the timestamp of yesterday at this time strtotime("-1 day")
Current time:
1.echo date("Y-m-d H:i:s",time( ))
Result: 2009-01-22 09:40:25
Specified time:
1.echo date("Y-m-d H:i:s",strtotime("-1 day"))
Result: 2009-01- 21 09:40:25
(3) Print the timestamp at this time next week strtotime("+1 week")
Current time:
1.echo date("Y-m-d H:i:s",time())
Result: 2009-01-22 09:40:25
Specified time:
1.echo date("Y-m-d H:i:s",strtotime("+1 week"))
Result: 2009-01-29 09 :40:25
(4) Print the timestamp at this time last week strtotime("-1 week")
Current time:
1.echo date("Y-m-d H:i:s",time())
Result ：2009-01-22 09:40:25
Specified time:
1.echo date("Y-m-d H:i:s",strtotime("-1 week"))
Result: 2009-01-15 09:40 :25
(5) Print the timestamp of the specified next day of the week strtotime("next Thursday")
Current time:
1.echo date("Y-m-d H:i:s",time())
Result: 2009-01 -22 09:40:25
Specified time:
1.echo date("Y-m-d H:i:s",strtotime("next Thursday"))
Result: 2009-01-29 00:00:00
(6 )Print the timestamp of the specified day of the week strtotime("last Thursday")
Current time:
1.echo date("Y-m-d H:i:s",time())
Result: 2009-01-22 09:40 :25
Specified time:
1.echo date("Y-m-d H:i:s",strtotime("last Thursday"))
Result: 2009-01-15 00:00:00
As can be seen from the above example, strtotime can The date and time description of any English text is parsed into a Unix timestamp. We combine mktime() or date() to format the date and time to obtain the specified timestamp and achieve the required date and time.
I hope that after the introduction of this article, you can master the usage of strtotime function.

The above introduces the use of the sumif function and a detailed explanation of the use of the strtotime function in PHP, including the use of the sumif function. I hope it will be helpful to friends who are interested in PHP tutorials.