为了我的需要，我需要安装PHP 7.4（和 Apache2 的模块），而不是最新的PHP 8.x。
因此我运行以下命令：apt-get install -y php7.4 libapache2-mod-php7.4
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Note, selecting 'libapache2-mod-php7.4' for regex 'php7.4'
Note, selecting 'php7.4-fpm' for regex 'php7.4'
Note, selecting 'php7.4-common' for regex 'php7.4'
The following additional packages will be installed:
libapache2-mod-php libapache2-mod-php8.1 php-common php8.1-cli php8.1-common php8.1-opcache php8.1-readline
Suggested packages:
php-pear
The following NEW packages will be installed:
libapache2-mod-php libapache2-mod-php7.4 libapache2-mod-php8.1 php-common php8.1-cli php8.1-common php8.1-opcache php8.1-readline
0 upgraded, 8 newly installed, 0 to remove and 0 not upgraded.
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Get:1 http://eu-frankfurt-1-ad-3.clouds.ports.ubuntu.com/ubuntu-ports jammy-updates/universe arm64 libapache2-mod-php7.4 arm64 8.1.2-1ubuntu2.2 [840 B]
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Setting up php8.1-opcache (8.1.2-1ubuntu2.2) ...
Setting up php8.1-cli (8.1.2-1ubuntu2.2) ...
update-alternatives: using /usr/bin/php8.1 to provide /usr/bin/php (php) in auto mode
update-alternatives: using /usr/bin/phar8.1 to provide /usr/bin/phar (phar) in auto mode
update-alternatives: using /usr/bin/phar.phar8.1 to provide /usr/bin/phar.phar (phar.phar) in auto mode
Setting up libapache2-mod-php8.1 (8.1.2-1ubuntu2.2) ...
apache2_invoke: Enable module php8.1
Setting up libapache2-mod-php7.4 (8.1.2-1ubuntu2.2) ...
Setting up libapache2-mod-php (2:8.1+92ubuntu1) ...
Processing triggers for man-db (2.10.2-1) ...
Processing triggers for php8.1-cli (8.1.2-1ubuntu2.2) ...
Processing triggers for libapache2-mod-php8.1 (8.1.2-1ubuntu2.2) ...
Scanning processes...
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Running kernel seems to be up-to-date.
No services need to be restarted.
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No VM guests are running outdated hypervisor (qemu) binaries on this host.
但是当我检查我安装的 PHP 版本时php --version，我得到了以下信息：
PHP 8.1.2 (cli) (built: Jul 21 2022 12:10:37) (NTS)
Copyright (c) The PHP Group
Zend Engine v4.1.2, Copyright (c) Zend Technologies
with Zend OPcache v8.1.2, Copyright (c), by Zend Technologies
问题
为什么PHP 8.1.2我明确尝试安装后还是会出现PHP 7.4？如何安装PHP 7.4后不留下任何痕迹PHP 8.x？
答案1
不是 100% 确定，但看起来你没有指定精确的软件包名称...我建议您通过命令
查找软件包名称 此外，您可能要查看您可能想要添加的模块（就您而言，我认为已经没问题了）。 有了这些，我认为您的最终安装命令行应该是： 无论如何，如果两个版本仍然继续安装，应该可以帮助您处理它。apt-cache policy php7.4*apt list |grep php7.4
sudo apt-get install -y php7.4-common libapache2-mod-php7.4
sudo update-alternative --config php
答案2
在您想要 php7.4 的目录中，创建一个 .htaccess 文件并在其中添加以下内容：
<FilesMatch "\.(php4|php5|php3|php2|php|phtml)$">
AddHandler application/x-httpd-php74 .php
</FilesMatch>
通常最好让最新的 php 版本在整个服务器上运行，并且只为每个子域、目录或您正在使用的任何文件添加特殊情况。