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PHP regular expression verification email address case

黄舟

Nov 11, 2017 am 10:50 AM

phpaddressexpression

php正则表达式使用有很多地方都可能使用的到，我们前面给大家介绍的是php正则表达式在某种模式，以及一个函数的解析，在我们工作中，我们经常会遇到验证邮箱，那么今天我们就带大家来了解下php正则表达式如何验证邮箱地址的！

网站上常见。各种网页脚本也都常用“正则表达式”（regular expression）对我们输入的电子邮件地址进行验证，判断是否合法。有的还能分解出用户名和域名。现在用PHP语言实现一下电子邮件地址验证程序，用的是PHP正则表达式库。

源代码如下：

<?php
  header ( "Content-Type: text/html; charset=UTF-8" );
  $reply = "";
  if ( isset($_POST["email_address"]) )
  {
    $email_address = $_POST["email_address"];
    $pattern = "/^([0-9A-Za-z\\-_\\.]+)@([0-9a-z]+\\.[a-z]{2,3}(\\.[a-z]{2})?)$/i";
    if ( preg_match( $pattern, $email_address ) )
    {
      $reply = "您输入的电子邮件地址合法<br /><br />\n";
      $user_name = preg_replace( $pattern ,"$1", $email_address );
      $domain_name = preg_replace( $pattern ,"$2", $email_address );
      $reply .= "用户名：".$user_name."<br />\n";
      $reply .= "域名：".$domain_name."<br />\n\n";
    }
    else
    {
      $reply = "您输入的电子邮件地址不合法";
    }
  }
?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" lang="zh" xml:lang="zh">
<head>
<title>电子邮件地址验证程序</title>
</head>
<body style="text-align: center;">
<h1 id="电子邮件地址验证程序">电子邮件地址验证程序</h1>
<form action="#" method="post">
请输入电子邮件地址：<input name="email_address" type="text" style="width: 300px;" /><br />
<input type="submit" value="验证电子邮件地址" />
</form>
<?php
  echo $reply;
?>
</body>
</html>

总结：

php正则表达式不仅仅可以验证邮箱地址，还是可以验证手机号等一些功能，所以大家可以根据本篇自己扩展，此篇做到抛砖引玉的效果，希望可以对你有所帮助！

相关推荐：

php正则表达式的实例分析

php正则表达式入门详解

一个最简单的PHP分页代码的简单实现

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