Php 如何将ereg_replace正则表达式转换为preg_replace

在此代码中，是否可以将ereg替换为preg值：

$phpAds_config['url_prefix'] = strtolower(eregi_replace("^([a-z]+)/.*$", "\\1://",
$HTTP_SERVER_VARS['SERVER_PROTOCOL'])) . $host .
ereg_replace("/admin/install.php(\?.*)?$", "", $HTTP_SERVER_VARS['PHP_SELF']);

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只需用分隔符围绕正则表达式：

$phpAds_config['url_prefix'] = strtolower(
    preg_replace("~^([a-z]+)/.*$~i", "\1://", $HTTP_SERVER_VARS['SERVER_PROTOCOL'])).
    $host. 
    preg_replace("~/admin/install.php(\?.*)?$~", "", $HTTP_SERVER_VARS['PHP_SELF']);