The factory model of PHP design mode and _php technique of single case mode

In this paper, we describe the design mode of PHP and the implementation of single example mode. Share to everyone for your reference, specific as follows:

Design patterns simply say the solution to a particular type of problem

Factory mode: create appropriate objects for requirements

Class factory{
  function __construct ($name) {
    if file_exists ('./'. $name. Class.php ') {return
      new $name;
    } else{
      die (' not exist ');}}

single case mode: creates only one instance of an object, does not allow the creation of instances, and saves resources (for example, connection to a database)

Class instance{public
  $val = ten;
  private static $instance;
  Private Function __construct () {}
  Private function __clone () {}
  //Set to static method to invoke public
  static function by class GetInstance () {
    /*if (!isset (self:: $instance)) {
      self:: $instance = new self;
    } *
    /if (!isset (instance:: $instance)) {
      instance:: $instance = new self;
    }
    Return instance:: $instance;
  }
}
$obj _one = Instance::getinstance ();
$obj _one->val =;
Clone can invoke __clone () to create a new object
//$obj _two = Clone $obj _one;
$obj _two = Instance::getinstance ();
echo $obj _two->val;
Echo ' <p> ';
Var_dump ($obj _one, $obj _two);

The results of the operation are as follows:

object (instance) [1] public
 ' val ' => int
(instance) [1] public
 ' val ' => int 20

Application: Database connection class (DB Access Oject)

Class mysqldb{Private $arr = Array (' Port ' => 3306, ' host ' => ' localhost ', ' username ' => ' root ',
  ' Passward ' => ' root ', ' dbname ' => ' instance ', ' CharSet ' => ' UTF8 ');
  Private $link;
  Static $instance; Private Function __clone () {} private Function __construct () {$this->link = mysql_connect ($this->arr[' host '), $t
    his->arr[' username '], $this->arr[' Passward ']) or Die (Mysql_error ());
    mysql_select_db ($this->arr[' dbname ']) or Die (' db error ');
  Mysql_set_charset ($this->arr[' CharSet ']);
    The static public function getinsance () {if (!isset (mysqldb:: $instance)) {mysqldb:: $instance = new Self;
  Return MYSQLDB:: $instance;
    Public Function Query ($sql) {if ($res = mysql_query ($sql)) {return $res;
  }return false;
    }//fetch one public function Get_one ($sql) {$res = $this->query ($sql);
    if ($result = Mysql_fetch_row ($res)) {return $result [0]; }}//fetch row
  Public Function Get_row ($sql) {$res = $this->query ($sql);
    if ($result = Mysql_fetch_assoc ($res)) {return $result;
  return false;
    //fetch All public Function Get_all ($sql) {$res = $this->query ($sql);
    $arr = Array ();
    while ($result = Mysql_fetch_assoc ($res)) {$arr [] = $result;
  return $arr;

 }} $mysql = Mysqldb::getinsance ();

More about PHP Interested readers can view the site topics: "PHP object-oriented Program Design Primer", "PHP basic Grammar Introductory Course", "PHP operation and operator Usage Summary", "PHP Network Programming Skills Summary", "PHP Array" operation Skills Encyclopedia, " Summary of PHP string usage, Introduction to PHP+MYSQL database operations, and a summary of PHP common database operations Tips

I hope this article will help you with the PHP program design.