PHP Object-oriented abstract class interface constant learning

 

Use and definition of PHP abstract class   <?php   abstract class A {   public $name;    function Fun () {&nbsp ;   Echo $this->name;   &NBSP}   abstract function cc ($n, $nn =3); &NBSP}  class B extends a{   function cc ($m, $mm =7) {   echo "AAA";    }  } &nbsp ; $b = new B;  ?> PHP Object-oriented, interface definition using <?php       interface in_a{    const na=7; const NB=9; &nb Sp  function Fun ();    function fun2 ();   &nbsp        interface in_b{    function fun3 ();    }    class b{    Function cc () {}        class A extends B implements in_a,in_b{    &NBSP ; function fun () {} function fun2 () {} function Fun3 () {}                 $p =new A;    ?>   Two examples:   abstract class Example:   <?php   abstract class mysql{    PUBlic $host//host address public $user;//user name public $passwd; Public $dbname; Public $charset;   function __construct ($h, $u, $p, $d, $c) {  $this->host= $h;   $this->user= $u;   $this-> Passwd= $p;   $this->dbname= $d;   $this->charset= $c;   $this->conn (); }   Function Conn () {@mysql_connect ($this->host, $this->user, $this->passwd) or Die ("MySQL connection failed") @mysql_ select_db ($this->dbname) or Die ("database connection failed"); $this->q ("Set Names '") $this->charset. "'"); }   function Q ($n) { return mysql_query ($n);}   function ID () { return mysql_insert_id ();}   FU Nction f ($n, $st =1) { switch ($st) { case 1:   $rs =mysql_fetch_array ($n);  break;  case 2:   $rs =mysql_fetch_row ($n);  break; return $rs; &NBSP}//========================/** * Description: Into Insert Database method * Parameter: $TB table name, $val for insert value, $st debug mode, 1 Debug 0 Debugging * return: int   *   & Nbsp;abstract function into ($TB, $val, $st =0);        /** * Description: Sel_oNCE query * Parameters: $TB table name, $WH conditions default 1, $ar set the field, $ty query type, default subscript and key name, $st debug state, default to 0, 1 Debug 0 Debug * return: Array [] / abstra CT function sel_once ($TB, $wh =1, $ar = "*", $ty =1, $st =0);      /** * Description: Sel_all query * Parameters: $TB table name, $WH conditions default 1, $ar set the field, $ty query type, default subscript and key name, $st debug state, default for 0, 1 Debug 0 Debug * return: Array [two-dimensional Array] /   abstract function Sel_all ($TB, $wh =1, $ar = "*", $ty =1, $st =0);      /** * Description: Update updates the database method * Parameters: $TB table name, $val update content $WH conditions [1 limit 1], $st debug mode default 0,1 debug 0 debugging * return: int   * * &NB Sp  abstract function Update ($TB, $val, $wh = "1 limit 1", $st =0);          /** * Description: Del Delete database method * Parameter: $TB table name, $WH condition [1 limit 1], $st debug mode default 0,1 debug 0 debugging * return: int  /& nbsp  abstract function del ($TB, $WH = "1 limit 1", $st =0); Learning examples for             { ?>   interface:   <?php   interface in_a{&nbsp ;  /**     Description: Login method Login     Parameters: $user username, $passwd password     return: BOOL [generate cookie]    */& NBsP  function Login ($user, $passwd); &NBSP}     Interface in_b{   /**     Description: Checklogin Check login     parameters: $n User default permissions 1 can specify different pages for User different permissions     return: bool    */  function checklogin ($n =1); &NBSP}     Interface in_c{   /**     Description: Checklogintime Check login timeout     Parameters: $ N is timeout default 3,600 sec     return: bool    */  function checklogintime ($n =3600); &NBSP}    //topic 1 Requirements: Landing page requires the use of In_a In_b interface  //Topic 2 requirements: After landing page requirements to use In_b In_c interface    ?>