PHP modifies the configuration in the config file

When developing a website using PHP, configuration files such as `config.php` typically require users to submit data through the backend for saving; in such cases, PHP is used to manipulate these files!

At this point, we need to use PHP to modify this PHP file.

For example, the code in my config.php file looks like this:

<?php
if(!defined('InEmpireCMS'))
{
	exit();
}
define('EmpireCMSConfig',TRUE);
$ecms_config=array();

//数据库设置
$ecms_config['db']['usedb']='mysql';	//数据库类型
$ecms_config['db']['dbver']='5.0';	//数据库版本
$ecms_config['db']['dbserver']='localhost';	//数据库登录地址
$ecms_config['db']['dbport']='';	//端口，不填为按默认
$ecms_config['db']['dbusername']='test_4s5_cn';	//数据库用户名
$ecms_config['db']['dbpassword']='wnxxtJTa3y4SPPrr';	//数据库密码
$ecms_config['db']['dbname']='test_4s5_cn';	//数据库名
$ecms_config['db']['setchar']='utf8';	//设置默认编码
$ecms_config['db']['dbchar']='utf8';	//数据库默认编码
$ecms_config['db']['dbtbpre']='phome_';	//数据表前缀
$dbtbpre=$ecms_config['db']['dbtbpre'];	//数据表前缀
$ecms_config['db']['showerror']=1;	//显示SQL错误提示(0为不显示,1为显示)

To make the change, I wrote a function!

function

function modifyDatabaseConfig($filename, $newConfig) {
  // 读取配置文件内容
  $file = file_get_contents($filename);
  // 替换配置内容
  
  // 配置文件里的变量名前缀
    $prefix = '$ecms_config[\'db\']';
    
    // 遍历新配置，将对应的变量替换为新值
    foreach ($newConfig as $key => $value) {
        $pattern = '/' . preg_quote($prefix) . '\[\'' . preg_quote($key) . '\'\]\s*=\s*\'[^;]+;/';
        $replace = $prefix . '[\'' . $key . '\'] = \'' . $value . '\';';
        $file = preg_replace($pattern, $replace, $file);
    }
  // 保存文件
  file_put_contents($filename, $file);
}

Function parameter description:

• $filename: The full path and filename of the configuration file;
• $newConfigAn array containing the database configuration items to be modified and their corresponding new values. For example, to change the database address to 127.0.0.1Change password newpasswordThe function can be called as follows:modifyDatabaseConfig('config.php', ['dbserver' => '127.0.0.1', 'dbpassword' => 'newpassword']);。

This function reads the contents of the configuration file, uses regular expressions to match all database configuration entries, replaces them with new values, and finally writes the modified content back to the configuration file.