PHP encapsulates mysqli Object Oriented mysql database operation classes and usage examples

This paper describes the PHP encapsulation mysqli based on object-oriented mysql database operation and usage. Share it for your reference, as follows:

First, encapsulate the mysql class

mysql.php

<?php
class Mysql{
     private static $host="localhost";
     private static $user="root";
     private static $password="123456";
     private static $dbName="test";           // Database name 
     private static $charset="utf8";          // Character encoding 
     private static $port="3306";            // Port number 
     private $conn=null;
     function __construct(){
       $this->conn=new mysqli(self::$host,self::$user,self::$password,self::$dbName,self::$port);
       if(!$this->conn)
       {
          die(" Database connection failed! ".$this->conn->connect_error);
       }else{
         echo " Connection succeeded! ";
       }
       $this->conn->query("set names ".self::$charset);
     }
     // Execute sql Statement 
     function sql($sql){
       $res=$this->conn->query($sql);
     if(!$res)
       {
          echo " Data operation failed ";
       }
       else
       {
          if($this->conn->affected_rows>0)
          {
             return $res;
          }
          else
          {
            echo "0 Row data is affected! ";
          }
       }
     }
     // Returns the number of affected data rows 
     function getResultNum($sql){
      $res=$this->conn->query($sql);
      return mysqli_num_rows($res);
      }
     // Close the database 
     public function close()
     {
       @mysqli_close($this->conn);
     }
}
?>

Then you can call

index.php

<?php
require_once "mysql.php";
$conn=new Mysql();
$sql="select * from user";
// Execute the query and get the query results 
$result=$conn->sql($sql);
// Output the number of affected data rows 
$num=$conn->getResultNum($sql);
echo " Number of rows affected: ".$num;
// Read and output records 
while ($row = mysqli_fetch_assoc($result))
{
  echo "{$row['name']} ";
  echo "{$row['password']}";
}
// Close the database 
$conn->close();

For more readers interested in PHP related contents, please check the topics on this site: "Summary of php+mysqli Database Programming Skills", "Introduction to php Object-Oriented Programming", "Encyclopedia of PHP Array (Array) Operation Skills", "Introduction to PHP Basic Syntax", "Summary of php String (string) Usage", "Introduction to php+mysql Database Operation Skills" and "Summary of php Common Database Operation Skills"

I hope this article is helpful to everyone's PHP programming.