Introduction to RewriteCond rule parameters in Apache_PHP tutorial

The RewriteCond statement in Apache has always been a difficulty for me. I have tried to figure it out many times, but there is no structure. This time I finally know what it means.
RewriteCond is just like the if statement in our program, which means that if one or several conditions are met, the RewriteRule statement immediately below RewriteCond will be executed. This is the most original and basic function of RewriteCond. In order to To facilitate understanding, let’s take a look at a few examples.

<span RewriteEngine on
RewriteCond  </span>%{HTTP_USER_AGENT}  ^Mozilla<span //</span><span 5/.0.*</span>
RewriteRule  index.php            index.m.<span php

RewriteCond  </span>%{HTTP_USER_AGENT}  ^Lynx.*<span 
RewriteRule  index</span>.php            index.L.<span php 

RewriteRule  index</span>.php            index.b.php

The function of the above statement is that when you use FF browser to access the index.php file, it will automatically allow you to access the index.m.php file. When you use some mobile When you access the file through the terminal, you will actually access index.L.php when accessing the file index.php. If you access it using another browser, you will be redirected to index.b.php. Speaking more vividly, the above statement is equivalent to the following statement in the program (take the PHP statement as an example):

<span if</span>(<span $_SERVER</span>['HTTP_USER_AGENT'] == 'Mozilla/5.0'<span )
{
</span><span //</span><span 跳转到对index.m.php的访问</span>
<span }
</span><span else</span> <span if</span>(<span $_SERVER</span>['HTTP_USER_AGENT'] == 'Lynx'<span )
{
</span><span //</span><span 跳转到对index.L.php的访问</span>
<span }
</span><span else</span>
<span //</span><span 跳转到对index.b.php的访问</span>

Looking at Example 2:
RewriteCond %{HTTP_REFERER} (www.test.cn)
RewriteRule (.*)$ test.php
The effect of the above statement is that if the host address of the previous page you visited is www.test.cn, no matter which page you are currently visiting, you will jump to the test .php access.

Looking at Example 3:

RewriteCond %{REMOTE_HOST} ^host1.*<span  [OR]
RewriteCond </span>%{REMOTE_HOST} ^host2.*<span  [OR]
RewriteCond </span>%{REMOTE_HOST} ^host3.*<span 
RewriteRule (</span>.*)$ test.php

The function of the above statement is that if your address is host1 or host2 or host3, it will jump to test.php. It can be seen from here that the default between RewriteCond statements is AND. If you want OR, you must write it explicitly.

Here are some useful rewrite rules that you have collected:


RewriteCond % {REQUEST_FILENAME} !-d //#If the directory exists, directly access the directory without performing RewriteRule

RewriteCond %{REQUEST_URI} !^.*(/.css|/. js|/.gif|/.png|/.jpg|/.jpeg)$ //#If it is a file with these suffixes, access the file directly without Rewrite