CodeIgniter项目本地运行遇HTTP Error 404资源未找到求助

Hey there, let's work through this 404 issue step by step—since you're new to CodeIgniter, we'll cover all the common pitfalls that cause this when running a friend's project locally with XAMPP.

1. Double-check your project's location in XAMPP #

First off, make sure your project is placed correctly in XAMPP's document root:

• XAMPP stores web-accessible files in the htdocs folder (usually C:\xampp\htdocs on Windows or /Applications/XAMPP/htdocs on Mac).
• If your project is in a subfolder like htdocs/my_ci_project, your access URL should be http://localhost:8000/my_ci_project/—not just localhost:8000. Skipping the subfolder is a super common first mistake!

2. Verify index.php path configurations #

Open your project's root index.php file and confirm these paths match your project structure:

• For CodeIgniter 3:
  • $system_path = 'system'; (must point to the core CodeIgniter system folder)
  • $application_folder = 'application'; (points to your app's code folder)
• For CodeIgniter 4:
  • $appPath = 'app'; (points to the main app directory)
  • $systemPath = 'system'; (core system folder)
    Typos or incorrect relative paths here will prevent CodeIgniter from loading its core files, leading straight to a 404.

3. Fix config.php settings #

You updated base_url, but let's make sure it's formatted correctly for your setup:

• For CI3:

  $config['base_url'] = 'http://localhost:8000/my_ci_project/'; // don't forget the trailing slash
  $config['index_page'] = ''; // set to empty to remove index.php from URLs
  $config['uri_protocol'] = 'REQUEST_URI'; // ensures proper URL parsing
  

• For CI4:

  public $baseURL = 'http://localhost:8000/my_ci_project/';
  public $indexPage = '';
  

4. Get .htaccess and mod_rewrite working #

URL rewriting (to remove index.php from URLs) is a frequent culprit for 404s:

1. Enable mod_rewrite in Apache:
   • Open XAMPP Control Panel → Click Config under Apache → Select httpd.conf
   • Find #LoadModule rewrite_module modules/mod_rewrite.so and remove the leading #
   • Save the file and restart Apache
2. Use the correct .htaccess for your CI version:
   • Place the file in your project's root (CI3) or the public folder (CI4):
     • CI3 .htaccess:

       RewriteEngine On
       RewriteCond %{REQUEST_FILENAME} !-f
       RewriteCond %{REQUEST_FILENAME} !-d
       RewriteRule ^(.*)$ index.php/$1 [L]
       

     • CI4 .htaccess:

       RewriteEngine On
       RewriteCond %{REQUEST_FILENAME} !-f
       RewriteCond %{REQUEST_FILENAME} !-d
       RewriteRule ^(.*)$ index.php/$1 [L]
       

   • If your project is in a subfolder, adjust the RewriteRule to include the folder name:

     RewriteRule ^(.*)$ /my_ci_project/index.php/$1 [L]
     

5. Check default routing #

Make sure your project has a valid default controller set:

• CI3: Open application/config/routes.php and confirm:

  $route['default_controller'] = 'Welcome'; // matches application/controllers/Welcome.php
  

  Ensure Welcome.php exists and has an index() method.
• CI4: Open app/Config/Routes.php and check:

  $routes->setDefaultController('Home'); // matches app/Controllers/Home.php
  

  Verify Home.php exists and extends BaseController.

6. Test the base access point #

As a quick sanity check, try accessing http://localhost:8000/my_ci_project/index.php directly. If this loads the default page, the issue is with URL rewriting (mod_rewrite or .htaccess). If this also throws a 404, go back and recheck your project path, index.php configurations, and base_url settings.

内容的提问来源于stack exchange，提问作者Zee