


Detailed explanation of date() function of PHP function_PHP tutorial
The date() function is a date function that we often encounter and use in PHP development. Now I will introduce to you some basic appearances and methods of the date() function. Friends who need to know more can refer to it.
Date and time functions are a core component of PHP. No installation is required to use these functions. Let’s talk about the specific usage of date function in detail:
PHP Date() function
The PHP Date() function formats a timestamp into a more readable date and time.
Grammar
date(format,timestamp)
format required. Specifies the format of the timestamp.
timestamp is optional. Specify timestamp. The default is the current date and time.
PHP date and time function date()
The code is as follows | Copy code | ||||
echo date("Y-m-d H:i:s",$t); |
The format of the first parameter respectively represents:
a - "am" or "pm"
A - "AM" or "PM"
d - day, two digits, if there are less than two digits, add zero in front; for example: "01" to "31"
D - day of the week, three English letters; such as: "Fri"
F - month, full English name; such as: "January"
h - hour in 12-hour format; e.g.: "01" to "12"
H - hour in 24-hour format; e.g.: "00" to "23"
g - hour in 12-hour format, no zeros are added if there are less than two digits; such as: "1" to 12"
G - hour in 24-hour format, no zeros are added if there are less than two digits; such as: "0" to "23"
i - minutes; e.g.: "00" to "59"
j - Day, two digits, if there are less than two digits, do not add zeros; for example: "1" to "31"
l - day of the week, full English name; such as: "Friday"
m - month, two digits, if there are less than two digits, add zeros in front; such as: "01" to "12"
n - month, two digits, if there are less than two digits, no zero will be added; for example: "1" to "12"
M - month, three English letters; such as: "Jan"
s - seconds; e.g.: "00" to "59"
S - add an English ordinal number at the end of the word, two English letters; such as: "th", "nd"
t - the number of days in the specified month; such as: "28" to "31"
U - Total seconds
w - Numeric day of the week, such as: "0" (Sunday) to "6" (Saturday)
Y - year, four digits; such as: "1999"
y - year, two digits; such as: "99" z - day of the year; e.g.: "0" to "365"
For other characters not listed above, list the character directly
代码如下 | 复制代码 |
echo date('Y-m-j'); 2007-02-6 echo date('y-n-j'); 07-2-6 |
The code is as follows | Copy code |
echo date('Y-m-j' ); 2007-02-6 echo date('y-n-j'); 07-2-6 |
代码如下 | 复制代码 |
echo date('Y-M-j'); 2007-Feb-6 echo date('Y-m-d'); 2007-02-06 |
The code is as follows | Copy code |
echo date('Y-M-j' ); 2007-Feb-6 echo date('Y-m-d'); 2007-02-06 |
Uppercase M represents the 3 abbreviated characters of the month, while lowercase m represents the number of the month (with leading 0);
There is no uppercase J, only lowercase j represents the day of the month, without the leading o; if a leading month is required, use a lowercase d.
The code is as follows | Copy code | ||||
echo date('Y-M-j' );
|
Capital M represents the 3 abbreviated characters of the month, while capital F represents the full English letter of the month. (no lowercase f) Capital S represents the suffix of the date, such as "st", "nd", "rd" and "th", depending on the date number.
Summary:
You can use uppercase Y or lowercase y to indicate the year;
Months can be represented by uppercase F, uppercase M, lowercase m and lowercase n (two ways to represent characters and numbers respectively);
Lowercase d and lowercase j can be used to represent the day, and uppercase S represents the suffix of the date.
2. Hour:minute:second
代码如下 | 复制代码 |
echo date('g:i:s a'); 5:56:57 am echo date('h:i:s A'); 05:56:57 AM |
The code is as follows | Copy code | ||||
echo date('g:i: s a'); 5:56:57 am
05:56:57 AM |
A lowercase g indicates a 12-hour clock without leading 0s, while a lowercase h indicates a 12-hour clock with leading 0s.
When using the 12-hour clock, it is necessary to indicate morning and afternoon. Lowercase a represents lowercase "am" and "pm", and uppercase A represents uppercase "AM" and "PM".
The code is as follows | Copy code |
echo date('G:i:s'); 14:02:26 |
Capital G represents the hour in 24-hour format, but without leading; use capital H to represent hour in 24-hour format with leading
Summary:
代码如下 | 复制代码 |
echo date('L'); 今年是否闰年:0 echo date('l'); 今天是:Tuesday echo date('D'); 今天是:Tue |
The letter g represents the hour without leading, and the letter h represents the hour with leading;
Lowercase g and h represent the 12-hour format, while uppercase G and H represent the 24-hour format.
3. Leap year, week, day
代码如下 | 复制代码 |
echo date('w'); |
The code is as follows | Copy code |
echo date('L'); Whether this year is a leap year: 0 echo date('l'); Today is: Tuesday echo date('D'); Today is: Tue |
The code is as follows | Copy code |
echo date('w'); |
Today’s week: 2
代码如下 | 复制代码 |
echo date('W'); |
This week is week 06 of the year
The lowercase w represents the day of the week, and the numeric form represents
Capital W represents the number of weeks in the year
The code is as follows | Copy code | ||||
|
This month is 28 days
The code is as follows | Copy code | ||||
|
Today is the 36th day of the year
Lowercase t represents the number of days in the current month
Lowercase z indicates what day of the year today is
4. Others
The code is as follows | Copy code | ||||
echo date('T');
|
Capital T indicates the server’s time locale
The code is as follows | Copy code | ||||
0 |
代码如下 | 复制代码 |
echo date('U'); 1170769424 |
The code is as follows | Copy code |
echo date('U'); 1170769424 |
代码如下 | 复制代码 |
echo date('c'); 2007-02-06T14:24:43+00:00 |
The code is as follows | Copy code | ||||
echo date('c');
|
The code is as follows | Copy code |
echo date('r'); Tue, 06 Feb 2007 14:25:52 +0000 |
Lowercase r indicates RFC822 date.

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