php timestamps are generally 10 digits. Method for calculating the number of digits in a PHP timestamp: 1. Use the time() function to obtain the current timestamp. The syntax "$time = time();" will return the integer value string of the UNIX timestamp; 2. Use the strlen() function Just find the length of the timestamp, the syntax is "$len=strlen($time);".
The operating environment of this tutorial: windows7 system, PHP8 version, DELL G3 computer
php timestamps are generally 10 digits .
Introduction to php timestamp
In the UNIX system, the date and time are expressed as since 00:00 on January 1, 1970 The total number of seconds from 00 minutes and 00 seconds (08:00 minutes and 00 seconds on January 1, 1970, Beijing time) to the current moment. This time is called a UNIX timestamp
UNIX time cutoff provides a A unified and concise time representation method is supported in different operating systems. The same time is represented by the same UNIX timestamp in UNIX and Windows systems, so there is no need to convert in different systems. At the same time, the UNIX timestamp is a time difference and has nothing to do with the time zone. No matter what time zone is currently used in PHP, its UNIX timestamp is unique.
PHP provides a variety of functions for processing UNIX timestamps. As of current PHP versions, times before January 1, 1970 cannot be represented in Windows since negative timestamps are not supported by any known version of Windows, and some other systems.
Because some operating systems currently use 32-bit binary numbers to represent time. UNIX timestamps for such systems can be used up to January 19, 2038 03:14:07 GMT (in binary: 01111111 11111111 11111111 11111111). The next second, the binary number will become 10000000 00000000 00000000 00000000, and an overflow error occurs, causing the system to misunderstand the time as December 13, 1901, 20 hours, 45 minutes and 52 seconds. This is likely to cause software failure or even system paralysis. Systems that use 64-bit binary numbers to represent time can be used up to 15:30:08 on December 04, 292277026596 Greenwich Mean Time, and basically will not encounter this type of overflow problem.
php gets the current timestamp and calculates the length
Step 1. Use the time() function to get the current timestamp
Use the time() function in PHP to obtain the current UNIX timestamp. The syntax format of the function is as follows:
time()
The time() function has no parameters and its return value is the UNIX timestamp. an integer value.
Example:
<?php header('content-type:text/html;charset=utf-8'); $time = time(); echo '当前的时间戳为:'.$time.'<br>'; ?>
Step 2: Use the strlen() function to find the length of the timestamp
The strlen() function can return a given string The length, the syntax format is as follows:
strlen($string)
The parameter $string is the string whose length needs to be calculated. Returns 0 if $string is empty.
Example:
<?php header('content-type:text/html;charset=utf-8'); $time = time(); echo '当前的时间戳为:'.$time.'<br>'; $len=strlen($time); echo '时间戳的长度:'.$len; ?>
Instructions:
In the strlen() function, numbers, English, decimal points, underscores and spaces occupy one character in length; while a GB2312 encoded Chinese character occupies two characters in length, and a UTF-8 encoded Chinese character occupies three characters in length.
Because the PHP timestamp is composed of numbers, it can be calculated using the strlen() function.
But if the string contains Chinese characters, you need to use the mb_strlen() function.
mb_strlen() function can calculate the length of English strings, Chinese strings or mixed Chinese and English strings. In the mb_strlen() function, whether it is Chinese characters, English characters, numbers, decimal points, underscores and spaces, they only occupy one character in length.
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