PHP 中的 NOW() 函数

NOW() function in PHP

提问by MoeAmine

Is there a PHP function that returns the date and time in the same format as the MySQL function NOW()?

是否有一个 PHP 函数以与 MySQL 函数相同的格式返回日期和时间NOW()？

I know how to do it using date(), but I am asking if there is a function only for this.

我知道如何使用date()，但我问是否有仅用于此的功能。

For example, to return:

例如，返回：

2009-12-01 00:00:00

回答by troelskn

Not besides the datefunction:

除了日期功能：

date("Y-m-d H:i:s");

回答by hsz

date('Y-m-d H:i:s')

Look here for more details: http://pl.php.net/manual/en/function.date.php

在这里查看更多详细信息：http: //pl.php.net/manual/en/function.date.php

回答by vascowhite

With PHP version >= 5.4 DateTimecan do this:-

使用 PHP 版本 >= 5.4 DateTime可以做到这一点：-

echo (new \DateTime())->format('Y-m-d H:i:s');

See it working.

看到它工作。

回答by user1786647

Use this function:

使用这个功能：

function getDatetimeNow() {
    $tz_object = new DateTimeZone('Brazil/East');
    //date_default_timezone_set('Brazil/East');

    $datetime = new DateTime();
    $datetime->setTimezone($tz_object);
    return $datetime->format('Y\-m\-d\ h:i:s');
}

回答by streetparade

Try this:

尝试这个：

date("Y-m-d H:i:s");

回答by Julian

Short answer

简答

$now = date_create()->format('Y-m-d H:i:s');

Read below for the long answer.

阅读下面的长答案。

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The mimicry of the MySQL NOW() function in PHP

PHP 中 MySQL NOW() 函数的模仿

Here is a list of ways in PHP that mimic the MySQL NOW()function.

这是 PHP 中模仿 MySQLNOW()函数的方法列表。

// relative date
$now = date_create('now')->format('Y-m-d H:i:s'); // works in php 5.2 and higher  
$now = date_create()->format('Y-m-d H:i:s'); // also works in php 5.2
$now = new DateTime('now')->format('Y-m-d H:i:s'); // syntax error!!!
$now = (new DateTime('now'))->format('Y-m-d H:i:s'); // works in php 5.4 and higher   
$now = date('Y-m-d H:i:s'); // Slightly higher performance, but less usable for date/time manipulations

// From Unix timestamp
// Using date_create() with a Unix timestamp will give you a FALSE,  
// and if you try to invoke format() on a FALSE then you'll get a: 
//     Fatal error: Call to a member function format() on boolean 
// So if you work with Unix timestamps then you could use: date_create_from_format().
$unixTimeStamp = 1420070400; // 01/01/2015 00:00:00
$y2015 = date_create_from_format('U', $unixTimeStamp, timezone_open('Europe/Amsterdam'))->format('Y-m-d H:i:s');
$y2015 = date('Y-m-d H:i:s', $unixTimeStamp);

I think that date_create()->format('Y-m-d H:i:s')is the best way because this approach allows you to handle time/time-zone manipulations easier than date('Y-m-d H:i:s')and it works since php 5.2.

我认为这date_create()->format('Y-m-d H:i:s')是最好的方法，因为这种方法使您可以比date('Y-m-d H:i:s')php 5.2更容易处理时间/时区操作，并且它可以工作。

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MySQL NOW() functionMySQL NOW() 函数

The MySQL function NOW()gives the dateTime value in this format: 'YYYY-MM-DD HH:MM:SS'. See here: https://dev.mysql.com/doc/refman/8.0/en/date-and-time-functions.html#function_now.

MySQL 函数NOW()以这种格式给出 dateTime 值：'YYYY-MM-DD HH:MM:SS'. 请参阅此处：https: //dev.mysql.com/doc/refman/8.0/en/date-and-time-functions.html#function_now。

An interesting fact is that it's possible to get the datetime format by running this query: SHOW VARIABLES LIKE 'd%e_format', the result could be something like this:

一个有趣的事实是，可以通过运行此查询来获取日期时间格式：SHOW VARIABLES LIKE 'd%e_format'，结果可能是这样的：

Variable_name     Value     
date_format       %Y-%m-%d
datetime_format   %Y-%m-%d %H:%i:%s

The variables up here are read-only variables. So you can't change it.

上面的变量是只读变量。所以你不能改变它。

I guess the MySQL NOW()function gets it's format from the datetime_formatvariable.

我猜 MySQLNOW()函数从datetime_format变量中获取它的格式。

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The advantages of date_create()->format() instead date() summary

date_create()->format() 代替 date() 的优点总结

The favorable facts of date_create('now')->format('Y-m-d H:i:s')over date('Y-m-d H:i:s')are:

date_create('now')->format('Y-m-d H:i:s')over的有利事实date('Y-m-d H:i:s')是：

• easier to handle time manipulations
• easier to handle timezones
• o.o.p.

• 更容易处理时间操作
• 更容易处理时区
• 哎呀

The disadvantages of date_create()->format() instead date()

date_create()->format() 代替 date() 的缺点

The function date()has a slightly better performance than date_create()->format(). See benchmark test below.

该函数的date()性能略好于date_create()->format(). 请参阅下面的基准测试。

$start = time();
for ($i = 0; $i <= 5000000; $i++) {
    $a = date_create('now')->format('Y-m-d H:i:s');
}
$end = time();                  
$elapsedTimeA = $end - $start;

echo 'Case A, elapsed time in seconds: ' . $elapsedTimeA;
echo '<br>';

$start = time();
for ($i = 0; $i <= 5000000; $i++) {
    $b = date('Y-m-d H:i:s');
}
$end = time();                   
$elapsedTimeB = $end - $start;

echo 'Case B, elapsed time in seconds: ' . $elapsedTimeB;
echo '<br>';
// OUTPUT
Case A, elapsed time in seconds: 31
Case B, elapsed time in seconds: 14

The upper case shows that date()is faster. However, if we change the test scenario a bit, then outcome will be different. See below:

大写字母表示date()速度更快。但是，如果我们稍微改变一下测试场景，那么结果就会有所不同。见下文：

$start = time();
$dt = date_create('now');
for ($i = 0; $i <= 5000000; $i++) {
    $a = $dt->format('Y-m-d H:i:s');
}
$end = time();                  
$elapsedTimeA = $end - $start;

echo 'Case A, elapsed time in seconds: ' . $elapsedTimeA;
echo '<br>';

$start = time();
for ($i = 0; $i <= 5000000; $i++) {
    $b = date('Y-m-d H:i:s');
}
$end = time();                   
$elapsedTimeB = $end - $start;

echo 'Case B, elapsed time in seconds: ' . $elapsedTimeB;
echo '<br>';
// OUTPUT
Case A, elapsed time in seconds: 14
Case B, elapsed time in seconds: 15

The DateTime method: format()is faster here than date().

DateTime 方法：format()在这里比date().

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The advantages of date_create()->format() instead date() detailed

date_create()->format()代替date()的优点详解

Read on for the detailed explanation.

请继续阅读以获取详细说明。

easier to handle time manipulations

更容易处理时间操作

date_create()accepts a relative date/time format (like now, yesterdayor +1 day) see this link, example:

date_create()接受相对日期/时间格式（如now,yesterday或+1 day）请参阅此链接，例如：

$tomorrow = date_create('+1 day')->format('Y-m-d H:i:s'); 

date()accepts a relative date/time format as well, like this:

date()也接受相对日期/时间格式，如下所示：

$tomorrow = date('Y-m-d H:i:s', strtotime('+1 day'));
$tomorrow = date('Y-m-d H:i:s', (time() + 86400)); // 86400 seconds = 1 day

easier to handle timezones

更容易处理时区

When timezones matter then the usage of date_create()->format()makes a lot more sense then date()because date()uses the default time zone which is configured in php.iniat the date.timezonedirective. Link: http://php.net/manual/en/datetime.configuration.php#ini.date.timezone.

当时区很重要时，那么使用date_create()->format()更有意义，date()因为date()使用php.ini在date.timezone指令中配置的默认时区。链接：http: //php.net/manual/en/datetime.configuration.php#ini.date.timezone。

It is possible to change the timezone during run-time. Example:

可以在运行时更改时区。例子：

date_default_timezone_set('Asia/Tokyo');.

date_default_timezone_set('Asia/Tokyo');.

The downside of that is that it will affect all date/time functions. This problem doesn't exists if you are using date_create()->format()in combination with timezone_open().

这样做的缺点是它会影响所有日期/时间函数。如果您date_create()->format()与timezone_open().

PHP supports major timezones. The funny thing is that it even supports the Arctic circle, and Antarctica. Have you ever heard about Longyearbyen? If not, then don't worry, neither did I until I read the official PHP documentation.

PHP 支持主要时区。有趣的是，它甚至支持北极圈和南极洲。你听说过Longyearbyen吗？如果没有，那么请不要担心，直到我阅读官方 PHP 文档之前我也没有。

$nowLongyearbyen = date_create('now', timezone_open('Arctic/Longyearbyen'))->format('Y-m-d H:i:s');

See a list of all supported timezones: http://php.net/manual/en/timezones.php.

查看所有支持的时区列表：http: //php.net/manual/en/timezones.php。

o.o.p.

哎呀

O.O.P. uses state-full Objects. So I prefer to think in this way:

OOP 使用全状态对象。所以我更喜欢这样思考：

// Create a DateTime Object. 
// Use the DateTime that applies for tomorrow.
// Give me the datetime in format 'Y-m-d H:i:s'
$tomorrow = date_create('+1 day')->format('Y-m-d H:i:s'); 

Then to think in this way:

然后这样想：

// Give me a date time string in format 'Y-m-d H:i:s', 
// use strtotime() to calculate the Unix timestamp that applies for tomorrow.
$tomorrow = date('Y-m-d H:i:s', strtotime('+1 day'));

Therefore I would say that the date_create()->format()approach is more readable to me then date().

因此，我会说这种date_create()->format()方法对我来说更具可读性date()。

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date_create() VS new DateTime()

date_create() VS new DateTime()

The favorable facts of date_create()over new DateTime()are:

date_create()over的有利事实new DateTime()是：

• Namespaces

• 命名空间

Namespaces

命名空间

If you work in a namespace and want to initialise a DateTime object with the new keyword, then you have to do it like this:

如果您在命名空间中工作并想使用 new 关键字初始化 DateTime 对象，那么您必须这样做：

namespace my_namespace;

// The backslash must be used if you are in a namespace.
// Forgetting about the backslash results in a fatal error.
$dt = new \DateTime();

There is nothing wrong with this, but the downside of the above is that people forget sporadically about the backslash. By using the date_create()constructor function you don't have to worry about namespaces.

这没有什么错，但上面的缺点是人们偶尔会忘记反斜杠。通过使用date_create()构造函数，您不必担心命名空间。

$dt = date_create(); // in or not in a namespace it works in both situations

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Example of date_create()->format()

date_create()->format() 示例

I use this approach for my projects if I have to fill an array. Like this:

如果我必须填充数组，我会在我的项目中使用这种方法。像这样：

$array = array(
    'name' => 'John',
    'date_time' => date_create('now')->format('Y-m-d H:i:s'), // uses the default timezone
    'date_time_japan' => date_create('now', timezone_open('Asia/Tokyo'))->format('Y-m-d H:i:s'),
);

回答by santi

I was looking for the same answer, and I have come up with this solution for PHP5.3 or later:

我一直在寻找相同的答案，我为PHP5.3 或更高版本提出了这个解决方案：

$dtz = new DateTimeZone("Europe/Madrid"); //Your timezone
$now = new DateTime(date("Y-m-d"), $dtz);
echo $now->format("Y-m-d H:i:s");

回答by Shriganesh Shintre

MySQL function NOW()returns the current timestamp. The only way I found for PHP is using the following code.

MySQL 函数NOW()返回当前时间戳。我为 PHP 找到的唯一方法是使用以下代码。

$curr_timestamp = date('Y-m-d H:i:s');

回答by Richard87

One more answer I find easy to use:

我发现另一个易于使用的答案：

echo date('c');

// 2015-07-27T00:00:00+02:00

This is ISO 8601 date (added in PHP 5)which MySQL uses

这是MySQL 使用的ISO 8601 日期（在 PHP 5 中添加）

Edit

编辑

MySQL 5.7 do not allow timezone in the datetime by default. You can disable the error with SQL_MODE=ALLOW_INVALID_DATES. See the answer here for more details: https://stackoverflow.com/a/35944059/2103434. But that also means that the timezone will be lost when saving to the database!

MySQL 5.7 默认不允许在日期时间中使用时区。您可以使用SQL_MODE=ALLOW_INVALID_DATES. 有关更多详细信息，请参阅此处的答案：https: //stackoverflow.com/a/35944059/2103434。但这也意味着保存到数据库时会丢失时区！

By default MySQL uses the system's timezone, and as long as PHP uses the same timezoneyou should be okay. In my case CET / UTC+2.

默认情况下 MySQL 使用系统的时区，只要 PHP 使用相同的时区，你应该没问题。就我而言，CET / UTC+2。

That means that if I insert 2015-07-27T00:00:00+02:00to the database, only 2015-07-27T00:00:00will be stored (but that is the correct local time!).

这意味着如果我插入2015-07-27T00:00:00+02:00到数据库中，只会2015-07-27T00:00:00被存储（但这是正确的本地时间！）。

When I load the time back in to PHP,

当我将时间加载回 PHP 时，

$importedDate = new \DateTime('2015-07-27T00:00:00')

it will automatically assume it's +02:00timezone since it's the default. Printing this will be correct again:

它会自动假定它是+02:00时区，因为它是默认的。打印这将再次正确：

echo $importedDate->format('c');
// 2015-07-27T00:00:00+02:00

To be safe, always use UTC on the server, specify it in MySQL and PHP, and then only convert it to your user's locale when displaying the date:

为安全起见，始终在服务器上使用 UTC，在 MySQL 和 PHP 中指定它，然后仅在显示日期时将其转换为用户的语言环境：

date_default_timezone_set('UTC');
$importedDate = new \DateTime('2015-07-27T00:00:00+02:00');
echo $importedDate->format('c');
// 2015-07-27T00:00:00+02:00

$importedDate->setTimezone(new \DateTimeZone("America/New_York"));
echo $importedDate->format('c');
// 2015-07-26T18:00:00-04:00

回答by Richard87

Use strftime:

使用strftime：

strftime("%F %T");

• %Fis the same as %Y-%m-%d.

• %Tis the same as %H:%M:%S.

• %F与 相同%Y-%m-%d。

• %T与 相同%H:%M:%S。

Here's a demoon ideone.

这是ideone上的演示。