PHP时间操作方法总结
php中如何获取当前的时间?
php如何获取当前时间戳?
首先需要知道的是在php中获取时间方法是date(),在php中获取时间戳方法有time()、strtotime()。
下面分别说明。date() 格式为:date($format, $timestamp),format为格式、timestamp为时间戳(可选)。time() 返回当前时间的 Unix 时间戳,没有参数。strtotime($time, $now) 将任何英文文本的日期时间描述解析为 Unix 时间戳。$time 为必填,规定要解析的时间字符串;$now 用来计算返回值的时间戳,如果省略该参数,则使用当前时间。date($format)用法举例:
echo date('Y-m-d');输出结果:2012-03-22
echo date('Y-m-d H:i:s');输出结果:2012-03-22 23:00:00
echo date('Y-m-d', time());输出结果:2012-03-22 23:00:00(结果同上,只是多了一个时间戳参数)(时间戳转换为日期格式的方法)
echo date('Y').'年'.date('m').'月'.date('d').'日',输出结果:2012年3月22日
举例就这几个,只是格式的变动而已,下面是字符串格式中各个字母的含义:a - "am" 或是 "pm"
A - "AM" 或是 "PM"
d - 几日,二位数字,若不足二位则前面补零; 如: "01" 至 "31"
D - 星期几,三个英文字母; 如: "Fri"
F - 月份,英文全名; 如: "January"
h - 12 小时制的小时; 如: "01" 至 "12"
H - 24 小时制的小时; 如: "00" 至 "23"
g - 12 小时制的小时,不足二位不补零; 如: "1" 至 12"
G - 24 小时制的小时,不足二位不补零; 如: "0" 至 "23"
i - 分钟; 如: "00" 至 "59"
j - 几日,二位数字,若不足二位不补零; 如: "1" 至 "31"
l - 星期几,英文全名; 如: "Friday"
m - 月份,二位数字,若不足二位则在前面补零; 如: "01" 至 "12"
n - 月份,二位数字,若不足二位则不补零; 如: "1" 至 "12"
M - 月份,三个英文字母; 如: "Jan"
s - 秒; 如: "00" 至 "59"
S - 字尾加英文序数,二个英文字母; 如: "th","nd"
t - 指定月份的天数; 如: "28" 至 "31"
U - 总秒数
w - 数字型的星期几,如: "0" (星期日) 至 "6" (星期六)
Y - 年,四位数字; 如: "1999"
y - 年,二位数字; 如: "99"
z - 一年中的第几天; 如: "0" 至 "365"time()用法举例:
time();输出结果:1332427715(返回的结果即当前的时间戳)strtotime($time)用法举例:echo strtotime('2012-03-22');输出结果:1332427715(此处结果为随便写的,仅作说明使用)
echo strtotime(date('Y-d-m'));输出结果:(结合date(),结果同上)(时间日期转换为时间戳)
strtotime()还有个很强大的用法,参数可加入对于数字的操作、年月日周英文字符,示例如下:
echo date('Y-m-d H:i:s',strtotime('+1 day'));输出结果:2012-03-23 23:30:33(会发现输出明天此时的时间)
echo date('Y-m-d H:i:s',strtotime('-1 day'));输出结果:2012-03-21 23:30:33(昨天此时的时间)
echo date('Y-m-d H:i:s',strtotime('+1 week'));输出结果:2012-03-29 23:30:33(下个星期此时的时间)
echo date('Y-m-d H:i:s',strtotime('next Thursday'));输出结果:2012-03-29 00:00:00(下个星期四此时的时间)
echo date('Y-m-d H:i:s',strtotime('last Thursday'));输出结果:2012-03-15 00:00:00(上个星期四此时的时间)以上举例就这么多了,更多的自己去变通研究吧,strtotime()方法可以通过英文文本的控制Unix时间戳的显示,而得到需要的时间日期格式。
php获取当前时间的毫秒数php本身没有提供返回毫秒数的函数,但提供了microtime()方法,它会返回一个数组,包含两个元素:一个是秒数、一个是小数表示的毫秒数,我们可以通过此方法获取返回的毫秒数,方法如下:
function getMillisecond(){<br /> list($s1,$s2)=explode(' ',microtime());<br /> return (float)sprintf('%.0f',(floatval($s1)+floatval($s2))*1000);<br /> }
获取的当前时间与实际时间相差8小时的解决方法实际开发中经常会碰到获取的时间与当前系统实际时间相差8个小时,这是因为时区设置问题,对于这个问题,有下面的几种解决办法:
1.在php.ini中找到date.timezone,将它的值改成 Asia/Shanghai,即 date.timezone = Asia/Shanghai(将当前时区设置为亚洲上海时区)
2.在程序开始的地方添加 date_default_timezone_set('Asia/Shanghai');即可。
好了,关于php获取当前时间、时间戳、毫秒数、时间差的总结,就写到这里了。有任何疑问,欢迎留言指正。

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