php regular expression application

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);

Generate random numbers

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);
//拆分字符串
//split()--js
echo "<br>";
var_dump(explode(&#39;b&#39;,$str2));
//链接字符
echo implode(&#39;|&#39;,["a","b","c"]);
替换字符串 查找替换
echo str_replace("cd","CD",$str2);
指定位置替换
echo substr_replace($str2,"xxx",0,3);
截取字符串
echo substr($str2,1,3);

The above is the detailed content of php regular expression application. For more information, please follow other related articles on the PHP Chinese website!