Detailed explanation of regular expression application in php
Regular expression
1. Replace "/\d/", "#", $str: regular expression\d number, replace with #, string
$str = "2hello 5li 6lei"; echo preg_replace("/\d/","#",$str);
2 , Split the regular expression, string
$str = "2hello 5li 6lei"; var_dump(preg_split("/\d/",$str));
3. Match all strings that satisfy the regular expression
$str = "2hello 5li 6lei"; preg_match_all("/\d",$str,$arr); //正则表达式,定义的字符串,数组 var_dump($arr); //匹配满足所有正则的字符串
4. Match the first string that satisfies the regular expression
$str = "2hello 5li 6lei"; preg_match("/\d/",$str,$arr); var_dump($arr);
生成随机数 echo rand(); echo "<br>"; echo rand(0,10); echo "<br>"; //获取当前时间 echo time(); echo "<br>"; //格式化显示时间 echo date("Y-m-d H:i:s","1506494423"); echo "<br>"; echo strtotime("2017-09-27 14:40:23"); 字符串函数 去字符串长度 $str1="as"; $str2="abcdecdcd"; //比较长度ASC代码 var_dump(strcmp($str2,$str1)); //显示长度 echo strlen($str);rrree
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