I have the following .htaccess file on my Apache Server, which does not work

我的Apache服务器上有以下.htaccess文件，该文件不起作用

<If "%{HTTP_HOST} == 'www.example.com'">
    RewriteCond %{REMOTE_ADDR} !^192\.168\.8\.8$
    RewriteRule .* - [F]

    RewriteRule ^([A-Za-z0-9_-]+)$ index.php?p=$1 [NC,L]

</If>

The code works fine without the if-Statement.
But with the if Statement

如果没有if语句，代码可以正常工作。但是使用if语句

    RewriteRule ^([A-Za-z0-9_-]+)$ index.php?p=$1 [NC,L]

does not work. It throws a "404 Not Found error"

不起作用。它抛出“404未找到错误”

<If "%{HTTP_HOST} == 'www.example.com'">
    RewriteCond %{REMOTE_ADDR} !^192\.168\.8\.8$
    RewriteRule .* - [F]

    RewriteRule ^([A-Za-z0-9_-]+)$ index.php?p=$1 [NC,L]

</If>

The "problem" is because the mod_rewrite directives are embedded inside an <If> expression. <If> blocks are merged very late, after the request has been mapped back to the file system. In this context, the RewriteRule pattern matches against the absolute filesystem path, not a relative URL-path, so the second rule above will not match as expected.

“问题”是因为mod_rewrite指令嵌入在 表达式中<如果>块在请求映射回文件系统后很晚才合并。在这种情况下，RewriteRule模式与绝对文件系统路径匹配，而不是与相对URL路径匹配，因此上面的第二条规则将不会像预期的那样匹配。

So, the rule would need to be rewritten like this instead:

因此，该规则需要像这样重写：

RewriteRule ^/abs/file/path/to/docroot/([A-Za-z0-9_-]+)$ index.php?p=$1 [L]

Or, more simply, remove the start-of-string anchor - although this does make the match somewhat ambiguous:

或者，更简单地说，删除字符串锚的开头——尽管这确实会使匹配变得有些模糊：

RewriteRule /([A-Za-z0-9_-]+)$ index.php?p=$1 [L]

Or, preferably, avoid the <If> construct altogether as you can get unexpected conflicts with other directives (outside of the <If> construct). For example:

或者，最好完全避免 构造，因为您可能会与其他指令（在 构造之外）发生意外冲突。例如：

RewriteCond %{HTTP_HOST} =www.example.com
RewriteCond %{REMOTE_ADDR} !^192\.168\.8\.8$
RewriteRule ^ - [F]

RewriteCond %{HTTP_HOST} =www.example.com
RewriteRule ^([A-Za-z0-9_-]+)$ index.php?p=$1 [L]

(The NC flag is not necessary in the 2nd rule, since you are already matching A-Z and a-z in the regex. ALso, use ^ instead of .* in the first rule, since you don't need to actually match anything here.)

（在第二条规则中不需要NC标志，因为您已经在正则表达式中匹配A-Z和A-Z。因此，在第一条规则中使用^而不是.*，因为您实际上不需要在这里匹配任何内容。）

If you have many such rules that apply to just this one host then you can reverse the logic and skip the N rules that follow when the requested host is not what is expected. For example:

如果您有许多这样的规则仅适用于这一台主机，那么当请求的主机不是预期的主机时，您可以颠倒逻辑，跳过后面的N条规则。例如：

# Skip the next 2 rules if the requested host is not "www.example.com"
RewriteCond %{HTTP_HOST} !=www.example.com
RewriteRule ^ - [S=2]

RewriteCond %{REMOTE_ADDR} !^192\.168\.8\.8$
RewriteRule ^ - [F]

RewriteRule ^([A-Za-z0-9_-]+)$ index.php?p=$1 [L]

I came myself to the following solutiuon. which i really like.

我自己找到了以下解决方案。我真的很喜欢。

### Access control
###
###
# Set the environment variable if the HTTP_HOST matches 'www.somehost.com'.
SetEnvIf Host "www\.somehost\.com" IS_HOST=true

# Use the set environment variable in a conditional
RewriteCond %{ENV:IS_HOST} true
RewriteCond %{REMOTE_ADDR} !^192\.168\.8\.8$
RewriteRule .* - [F]



### Rewrite Urls
###
###
RewriteRule ^([A-Za-z0-9_-]+)$ index.php?p=$1 [NC,L]