PHP Date Operation techniques Summary _php Tips

This example summarizes the PHP date manipulation techniques. Share to everyone for your reference, specific as follows:

1. PHP converts the date format obtained in the form into a unified format

2015-9-9 is unified into 2015-09-09 so in the database are unified format, easy to query later

$year = "2015";
$month = "9";
$day = "a";
Var_dump (Checkdate ($month, $day, $year))//month and day with leading 0 are in line with the format
if (Checkdate ($month, $day, $year) ===false) {
  Exit (' error ');
$unixtime = Mktime (2,2,2, $month, $day, $year);//The purpose is to convert PHP into months and days with a format of leading 0 in a uniform format stored in the database to facilitate query
Var_dump (date ("y-m-d" , $unixtime));
Convert PHP to timestamp, then reverse back

2. Get start time stamp and end timestamp for last day

Originally thought is:

Use date to get the date of the day. Individually acquired. The year is 2015 months, 9th is 28.
And then minus 1 is OK. But the problem comes out.

If today is number 1th. Minus 1 becomes 0. Last month could have been 28 days, or 30 days.

In this way, get the time stamp of the previous day first. Let PHP automatically compute.

Strtotime ("-1 day");
Get the time stamp of the day, now is the time to get the time stamp of this point in the day, in this way the advantage is to solve the above problem, PHP will automatically calculate how many days last month

<?php
Header ("Content-type:text/html;charset=utf-8");
Date_default_timezone_set ("Asia/shanghai");/set time zone
$last _day = Strtotime ("-1 day"); Now is the time to get the last day of this point timestamp
//time stamp to get the month and year, so that mktime use
$year = Date ("Y", $last _day);
$month = Date ("M", $last _day);
$day = Date ("D", $last _day);
$last _day_begin = Mktime (0,0,0, $month, $day, $year); the timestamp of yesterday's day began
$last _day_end = Mktime (23,59,59, $month, $day, $ year);
Echo ' Yesterday started time stamp: ';
Var_dump ($last _day_begin);
echo Date (' y-m-d h:i:s ', $last _day_begin);
echo ' <br/> ';
Echo ' Yesterday's End time stamp: ';
Var_dump ($last _day_end);
echo Date (' y-m-d h:i:s ', $last _day_end);
echo ' <br/> ';
Echo ($last _day_end-$last _day_begin)/(60*60);//exactly 24 hours

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I hope this article will help you with the PHP program design.