如何使用 substr 和 strrpos 来清理特定字符后的字符串？

Question

我想从以下字符串中删除我设置的关键字之后的任何内容。请记住， url 变量只是一个示例，在现实生活中它可以采用多种形式。例如，以下，$url = '/resutls?offer=1&gclid=CjwKCAjw1f_pBRAEEiwApp0JK';我希望它是/resutls?offer=1但是当我使用以下代码时$url = substr($url, 0, strrpos( $url, '&gclid'));$url = substr($url, 0, strrpos( $url, '&utm_source'));$url = substr($url, 0, strrpos( $url, '?utm_campaign'));$url = substr($url, 0, strrpos( $url, '?utm_medium'));$url = substr($url, 0, strrpos( $url, '?token'));$url = substr($url, 0, strrpos( $url, '&fbclid'));$url = substr($url, 0, strrpos( $url, '&utm_campaign'));$url = substr($url, 0, strrpos( $url, '&utm_medium'));$url = substr($url, 0, strrpos( $url, '&token'));echo $url;url 变量返回空。我怎样才能解决这个问题？

Answer 1

尝试这个

<?php

$url = '/resutls?offer=1&gclid=1&utm_source=21213';

$url = strrpos( $url, '&gclid')?substr($url, 0, strrpos( $url, '&gclid')):$url; 

$url = strrpos( $url, '&utm_source')?substr($url, 0, strrpos( $url, '&utm_source')):$url; 

$url = strrpos( $url, '?utm_campaign')?substr($url, 0, strrpos( $url, '?utm_campaign')):$url;

$url = strrpos( $url, '?utm_medium')?substr($url, 0, strrpos( $url, '?utm_medium')):$url;

$url = strrpos( $url, '?token')?substr($url, 0, strrpos( $url, '?token')):$url;

$url = strrpos( $url, '&fbclid')?substr($url, 0, strrpos( $url, '&fbclid')):$url;

$url = strrpos( $url, '&utm_campaign')?substr($url, 0, strrpos( $url, '&utm_campaign')):$url;

$url = strrpos( $url, '&utm_medium')?substr($url, 0, strrpos( $url, '&utm_medium')):$url;

$url = strrpos( $url, '&token')?substr($url, 0, strrpos( $url, '&token')):$url;

echo $url;

?>

Answer 2

使用parse_url()和parse_str()获取您想要的任何关键字。

$parsed = parse_url('/resutls?offer=1&gclid=CjwKCAjw1f_pBRAEEiwApp0JK');

parse_str($parsed['query'], $output);

echo($output['offer']);  // should print 1

您也可以使用它来重建您的 URL：

echo $parsed['path'] . '?offer=' . $output['offer']; // prints /resutls?offer=1

Answer 3

我已经将“如果找到后删除”包装到一个函数中。这首先检查字符串是否存在，然后如果存在，它将执行该substr()部分...

function trimIfSet ( string $base, string $pattern )   {

    if (( $pos = strrpos($base, $pattern)) !== false ){

        $base = substr($base, 0, $pos);

    }

    return $base;

}

$url = '/resutls?offer=1&gclid=CjwKCAjw1f_pBRAEEiwApp0JK';

$url = trimIfSet( $url, '&gclid');

$url = trimIfSet( $url, '&utm_source');

echo $url;