Why do website not show after uploaded to host?

I has used FileZilla upload all source code of website to host, has imported database successfully, and deleted file default.php in folder public_html , but when I enter the website address, it only shows file welcome.php like this:
Welcome to CodeIgniter!
The page you are looking at is being generated dynamically by CodeIgniter.
If you would like to edit this page you'll find it located at:
application/views/welcome_message.php
The corresponding controller for this page is found at:
application/controllers/welcome.php
If you are exploring CodeIgniter for the very first time, you should start by reading the User Guide.
After I set ../application/config/routes.php like this :

PHP Code:

$route['default_controller'] = "cHome"; 


cHome is controller of home page of website, it shows error like this :
404 Page Not Found

The page you requested was not found.
I've replaced the other controllers on it but still have the same result, try site_url() or base_url() function, it shows error like this function is not defined. Source I uploaded not to modify configuration anything. I don't understand why. Everybody help me. Thanks!

Your should check out your configurations (are your using 'index.php' in your url) I think you should write chome instead of cHome, some server are case sensitive.

Is your website working on local server ?

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I has used FileZilla upload all source code of website to host, has imported database successfully, and deleted file default.php in folder public_html , but when I enter the website address, it only shows file welcome.php like this:
Welcome to CodeIgniter!
The page you are looking at is being generated dynamically by CodeIgniter.
If you would like to edit this page you'll find it located at:
application/views/welcome_message.php
The corresponding controller for this page is found at:
application/controllers/welcome.php
If you are exploring CodeIgniter for the very first time, you should start by reading the User Guide.  
After I set ../application/config/routes.php like this :

PHP Code:

$route['default_controller'] = "cHome";   


cHome is controller of home page of website, it shows error like this :
404 Page Not Found

The page you requested was not found.
I've replaced the other controllers on it but still have the same result, try site_url() or base_url() function, it shows error like this function is not defined. Source I uploaded not to modify configuration anything. I don't understand why. Everybody help me. Thanks!

I would change the controller to some thing like Chome.php

PHP Code:

<?php

class Chome extends CI_Controller {
   public function index() {
   }
} 


Then routes $route['default_controller'] = "chome";

or

$route['default_controller'] = "chome/index";

There's only one rule - please don't tell anyone to go and read the manual.  Sometimes the manual just SUCKS!

Your should check out your configurations (are your using 'index.php' in your url) I think you should write chome  instead  of cHome, some server are case sensitive.

Is your website working on local server ?

Here is my configurations in file config.php :

PHP Code:

$config['base_url']    = 'http://nhacchonloc.zz.mu';
$config['index_page'] = '';
$config['uri_protocol']    = 'AUTO';
... 


I'm using free host of Hostinger,domain is 'http://nhacchonloc.zz.mu'. I changed 'cHome' to 'chome' as the same that you said, or changed

PHP Code:

$config['index_page'] = ''; 


to 

PHP Code:

$config['index_page'] = 'index.php'; 


but the result still was not changed anything. 
When I entered the address URL is 'nhacchonloc.zz.mu/index.php/cHome', home page was showed, but when I redirected to the other page, any the page,  it showed "error_404?"

I has used FileZilla upload all source code of website to host, has imported database successfully, and deleted file default.php in folder public_html , but when I enter the website address, it only shows file welcome.php like this:
Welcome to CodeIgniter!
The page you are looking at is being generated dynamically by CodeIgniter.
If you would like to edit this page you'll find it located at:
application/views/welcome_message.php
The corresponding controller for this page is found at:
application/controllers/welcome.php
If you are exploring CodeIgniter for the very first time, you should start by reading the User Guide.  
After I set ../application/config/routes.php like this :

PHP Code:

$route['default_controller'] = "cHome";   


cHome is controller of home page of website, it shows error like this :
404 Page Not Found

The page you requested was not found.
I've replaced the other controllers on it but still have the same result, try site_url() or base_url() function, it shows error like this function is not defined. Source I uploaded not to modify configuration anything. I don't understand why. Everybody help me. Thanks!

I would change the controller to some thing like Chome.php

PHP Code:

<?php

class Chome extends CI_Controller {
   public function index() {
   }
} 


Then routes $route['default_controller'] = "chome";

or

$route['default_controller'] = "chome/index";

My controller cHome.php like this :

PHP Code:

class CHome extends CI_Controller{
    public function __construct() {
        parent::__construct();
    }
     
    public function index(){
    ...
    }
} 


Regardless I configured file routes.php like this :

PHP Code:

$route['default_controller'] = "cHome"; 


or 

PHP Code:

$route['default_controller'] = "chome"; 


the result was still not changed.

Controller file/class names are supposed to be ucfirst, i.e. Chome.php, not cHome.php or chome.php.

You might be able to get away with CHome.php, but I wouldn't depend on it.

In most cases, the names in the configuration files can be all lowercase.

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