PHP正则表达式(常用的7个例子)_PHP教程-php教程-PHP中文網

PHP正则表达式(常用的7个例子)_PHP教程

WBOY

發布： 2016-07-13 09:56:25

原創

850 人瀏覽過

PHP正则表达式(常用的7个例子)

1、验证E-mail

用filer_var 比用正则匹配更加好

if (filter_var(&#39;test+email@ansoncheung&#39;, FILTER_VALIDATE_EMAIL)) {
    echo "Your email is ok.";
} else {
    echo "Wrong email address format.";
}

登入後複製

2、验证用户名(验证用户名5-20之间)

$username = "user_name12";
if (preg_match(&#39;/^[a-z\d_]{5,20}$/i&#39;, $username)) {
    echo "Your username is ok.";
} else {
    echo "Wrong username format.";
}

登入後複製

3、验证ip地址

$IP = "198.168.1.78";
if (preg_match(&#39;/^(([1-9]?[0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5]).){3}([1-9]?[0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])$/&#39;,$IP)) {
    echo "Your IP address is ok.";
} else {
    echo "Wrong IP address.";
}

登入後複製

4、验证邮编

$zipcode = "12345-5434";
 if (preg_match("/^([0-9]{5})(-[0-9]{4})?$/i",$zipcode)) {
 echo "Your Zip code is ok.";
 } else {
 echo "Wrong Zip code.";
 }

登入後複製

5、验证域名

$url = "http://ansoncheung.tk/";
 if (preg_match(&#39;/^(http|https|ftp):\/\/([A-Z0-9][A-Z0-9_-]*(?:\.[A-Z0-9][A-Z0-9_-]*)+):?(\d+)?\/?/i&#39;, $url)) {
 echo "Your url is ok.";
 } else {
 echo "Wrong url.";
 }

登入後複製

6、从特定URL中提取域名

$url = "http://ansoncheung.tk/articles";
 preg_match(&#39;@^(?:http://)?([^/]+)@i&#39;, $url, $matches);
 $host = $matches[1];
echo $host;

登入後複製

7、文本中关键字高亮显示

$text = "Sample sentence from AnsonCheung.tk, regular expression has become popular in web programming. Now we learn regex. According to wikipedia, Regular expressions (abbreviated as regex or regexp, with plural forms regexes, regexps, or regexen) are written in a formal language that can be interpreted by a regular expression processor";
$text = preg_replace("/\b(regex)\b/i", &#39;<span style="background:#5fc9f6">\1</span>&#39;, $text);
echo $text;

登入後複製