[php]php设计模式 Factory(工厂模式)

<?php
 2 /**
 3  * 工厂方法模式
 4  *
 5  * 定义一个用于创建对象的接口,让子类决定将哪一个类实例化,使用一个类的实例化延迟到其子类
 6 */
 7 
 8 /*
 9 class DBFactory
10 {
11     public static function create($type)
12     {
13         swtich($type)
14         {
15             case "Mysql":
16                 return new MysqlDB(); break;
17             case "Postgre":
18                 return new PostgreDB(); break;
19             case "Mssql":
20                 return new MssqlDB(); break;
21         }
22     }
23 }
24 */
25 class DBFactory
26 {
27 publicstaticfunction create($type)
28     {
29 $class=$type."DB";
30 returnnew$class;
31     }
32 }
33 
34 interface DB
35 {
36 publicfunction connect();
37 publicfunctionexec();
38 }
39 
40 class MysqlDB implements DB
41 {
42 publicfunction __construct() {
43 echo"mysql db<br/>";
44     }
45 
46 publicfunction connect() {
47     }
48 
49 publicfunctionexec() {
50     }
51 }
52 
53 class PostgreDB implements DB
54 {
55 publicfunction __construct() {
56 echo"Postgre db<br/>";
57     }
58 
59 publicfunction connect() {
60     }
61 
62 publicfunctionexec() {
63     }
64 }
65 
66 class MssqlDB implements DB
67 {
68 publicfunction __construct() {
69 echo"mssql db<br/>";
70     }
71 
72 publicfunction connect() {
73     }
74 publicfunctionexec() {
75     }
76 }
77 
78 
79 $oMysql= DBFactory::create("Mysql");
80 $oPostgre= DBFactory::create("Postgre");
81 $oMssql= DBFactory::create("Mssql");