PHP implementation example of modifying the configuration file

Let’s take a look at the installation interface of discuz, a well-known domestic forum:

If you install it here, why does it modify the config.inc.php file?

Let’s use a few simple techniques to uncover its so-called mystery!

File planning:

1.index.php -- Display modification interface

2.edit.php -- Modify function code

3.config .php -- the actual modification part

index.php displays the modification interface. Display the configuration items in config.php. Displayed in the form:

2.edit.php Read the config.php file and treat this file as a string. I then use regular expression matching to modify the content.

$val){ //定义正则来查找内容，这里面的key为form表单里面的name $yx="/define\('$key','.*?'\);/"; //将内容匹配成对应的key和修改的值 $re="define('$key','$val');"; //替换内容 $string=preg_replace($yx,$re,$string); } //写入成功 file_put_contents('config.php',$string); echo '修改成功'; ?>

config.php The part that actually stores the configuration file stores the real config.php file content:

Have you discovered that this is not as difficult as you thought. Combined with the knowledge of regular expression expressions and files, you can do it!