define('WP_HOME','http://example.com');
define('WP_SITEURL','http://example.com');

// Add to top of wp-config.php
define( 'WP_HOME', 'http://example.com' );
define( 'WP_SITEURL', 'http://example.com' );

$url = home_url();
echo $url; // Output: http://www.example.com
$url = home_url( '/' );
echo $url; // Output: http://www.example.com/
$url = home_url( $path = '/', $scheme = 'https' );
echo $url; // Output: https://www.example.com/
$url = home_url( $path = 'example', $scheme = 'relative' );
echo $url; // Output: /example

//It is possible to set the site URL manually in the wp-config.php file.
//Add these two lines to your wp-config.php, where “example.com” is the correct location of your site.
define( 'WP_HOME', 'http://example.com' );
define( 'WP_SITEURL', 'http://example.com' );
//Important! Do not leave this code in the functions.php file. Remove them after the site is up and running again.
update_option( 'siteurl', 'http://example.com' );
update_option( 'home', 'http://example.com' );

/*	Method 1: Adding some code to the wp-config file. These lines can be added before the line that says "That's all, stop editing! Happy publishing"
*/
define( 'WP_HOME', 'http://example.com' );
define( 'WP_SITEURL', 'http://example.com' );
/*	Method 2: Update the DB entries by adding some code (temporarily) to the functions.php file. Important: Do not forget to remove these lines of code once the site is up and running. It is a security risk. Try adding the below lines to the end of your functions.php file.
*/
update_option( 'siteurl', 'http://example.com' );
update_option( 'home', 'http://example.com' );