<?php
    class connect_db
    {
        const DB_HOST = 'localhost';
        const DB_USER = 'root';
        const DB_PASSWORD = '';
        const DATABASE = 'yourblog';
        protected $mysqLi;
        function __construct()
        {
            $this->mysqLi = new mysqli(self::DB_HOST,self::DB_USER,self::DB_PASSWORD,self::DATABASE);
            $this->mysqLi->query ("set character_set_client='utf8'");
            $this->mysqLi->query ("set character_set_results='utf8'");
            $this->mysqLi->query('SET CHARACTER SET utf8');
            $this->mysqLi->query('SET NAMES utf8');
        }
    }

    $connect_db = new connect_db();
?>