Php 从一堆字符串创建url链接

我有一堆字符串连接在一起，形成一个包含文本和链接的字符串。我想在字符串中查找URL，并想将

href

放到每个URL中（创建链接）。我使用正则表达式模式查找字符串中的URL（链接）。请查看下面的示例：

例如：

    <?php

// The Text you want to filter for urls
        $text = "The text you want to filter goes here. http://google.com/abc/pqr
2The text you want to filter goes here. http://google.in/abc/pqr
3The text you want to filter goes here. http://google.org/abc/pqr
4The text you want to filter goes here. http://www.google.de/abc/pqr";

// The Regular Expression filter
        $reg_exUrl = "/(http|https|ftp|ftps)\:\/\/[a-zA-Z0-9\-\.]+\.[a-zA-Z]{2,3}(\/\S*)?/";


// Check if there is a url in the text
        if (preg_match($reg_exUrl, $text, $url)) {
            // make the urls hyper links
            echo preg_replace($reg_exUrl, "<a href='.$url[0].'>" . $url[0] . "</a> ", $text);
        } else {
            // if no urls in the text just return the text
            echo $text . "<br/>";
        }
        ?>

---

这有什么问题

由于正则表达式是用斜杠分隔的，所以当正则表达式包含斜杠时需要非常小心。通常，使用不同的字符来分隔正则表达式更容易：PHP并不介意您使用什么

尝试将第一个和最后一个“/”字符替换为另一个字符，例如“#”，您的代码可能会正常工作

您还可以简化代码，通过调用preg_replace完成整个过程，如下所示：

<?php

$text = 'The text you want to filter goes here. http://google.com/abc/pqr
    2The text you want to filter goes here. http://google.in/abc/pqr
    3The text you want to filter goes here. http://google.org/abc/pqr
    4The text you want to filter goes here. http://www.google.de/abc/pqr';

echo preg_replace('#(http|https|ftp|ftps)\://[a-zA-Z0-9-.]+.[a-zA-Z]{2,3}(/\S*)?#i', '<a href="$0">$0</a>', $text);

---

如果不使用占位符语法，请使用
preg\u replace\u callback
。还有现有的“linkify”工具。在博客帖子中的解决方案评论中有更多的解决方案本身也不起作用。
<?php

$text = 'The text you want to filter goes here. http://google.com/abc/pqr
    2The text you want to filter goes here. http://google.in/abc/pqr
    3The text you want to filter goes here. http://google.org/abc/pqr
    4The text you want to filter goes here. http://www.google.de/abc/pqr';

echo preg_replace('#(http|https|ftp|ftps)\://[a-zA-Z0-9-.]+.[a-zA-Z]{2,3}(/\S*)?#i', '<a href="$0">$0</a>', $text);