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<?php header("Content-type:text/html;charset=utf-8"); /** * db接口 * 实现连接数据库函数conn */ interface db { function conn(); } /** * 工厂接口 * 实现创建连接函数createDb */ interface factory { function createDb(); } /** * mysql类 */ class DbMysql implements db { public function conn() { echo "连接上了mysql<br>"; } } /** * sqlite类 */ class DbSqlite implements db { public function conn() { echo "连接上了sqlite<br>"; } } /** * MysqlFactory */ class MysqlFactory implements factory { public function createDb() { return new DbMysql(); } } /** * SqliteFactory */ class SqliteFactory implements factory { public function createDb() { return new DbSqlite(); } } //不改削源代码，，扩展oracle数据库 /** * oracle */ class DbOracle implements db { public function conn() { echo "连上了oracle数据库<br>"; } } /** * oracle工厂类 */ class OracleFactory implements factory { public function createDb() { return new DbOracle(); } } // 客户端挪用 $factory = new MysqlFactory(); $db = $factory->createDb(); $db->conn(); $factory = new SqliteFactory(); $db = $factory->createDb(); $db->conn(); $factory = new OracleFactory(); $db = $factory->createDb(); $db->conn();

php设计模式之工厂要领