php缓存数据功能的mysqli类

1. <?php    
2.     /**   
3.     * Mysqli类   
4.     *   
5.     * @author 废墟   
6.     * @version v1.0 2009-08-18  
7.     */    
8.     class db_mysqli {    
9.         protected $mysqli;    
10.         protected $sql;    
11.         protected $rs;    
12.         protected $query_num    = 0;    
13.         protected $fetch_mode    = MYSQLI_ASSOC;    
14.         protected $cache_dir    = './cache/';    
15.         protected $cache_time    = 1800;    
16.   
17.         public function  __construct($dbhost, $dbuser, $dbpass, $dbname) {    
18.             $this->mysqli    = new mysqli($dbhost, $dbuser, $dbpass, $dbname);    
19.             if(mysqli_connect_errno()) {    
20.                 $this->mysqli    = false;    
21.                 echo '<h2>'.mysqli_connect_error().'</h2>';    
22.                 die();    
23.             } else {    
24.                 $this->mysqli->set_charset("utf8");    
25.             }    
26.         }    
27.   
28.         public function  __destruct() {    
29.             $this->free();    
30.             $this->close();    
31.         }    
32.   
33.         protected function free() {    
34.             @$this->rs->free();    
35.         }    
36.   
37.         protected function close() {    
38.             $this->mysqli->close();    
39.         }    
40.   
41.         protected function fetch() {    
42.             return $this->rs->fetch_array($this->fetch_mode);    
43.         }    
44.   
45.         protected function getQuerySql($sql, $limit = null) {    
46.             if (@preg_match("/[0-9]+(,[ ]?[0-9]+)?/is", $limit) && !preg_match("/ LIMIT [0-9]+(,[ ]?[0-9]+)?$/is", $sql)) {    
47.                 $sql .= " LIMIT " . $limit;    
48.             }    
49.             return $sql;    
50.         }    
51.   
52.         protected function get_cache($sql,$method) {    
53.             include_once './cache.php';//若框架中使用__autoload()，这里可以不用加载文件    
54.             $cache    = new cache($this->cache_dir,$this->cache_time);    
55.             $cache_file    = md5($sql.$method);    
56.             $res    = $cache->get_cache($cache_file);    
57.             if(!$res) {    
58.                 $res    = $this->$method($sql);    
59.                 $cache->set_cache($cache_file, $res);    
60.             }    
61.             return $res;    
62.         }    
63.   
64.         public function query_num() {    
65.             return $this->query_num;    
66.         }    
67.   
68.         public function set_cache_dir($cache_dir) {    
69.             $this->cache_dir    = $cache_dir;    
70.         }    
71.   
72.         public function set_cache_time($cache_time) {    
73.             $this->cache_time    = $cache_time;    
74.         }    
75.   
76.         public function query($sql, $limit = null) {    
77.             $sql    = $this->getQuerySql($sql, $limit);    
78.             $this->sql    = $sql;    
79.             $this->rs    = $this->mysqli->query($sql);    
80.             if (!$this->rs) {    
81.                 echo "<h2>".$this->mysqli->error."</h2>";    
82.                 die();    
83.             } else {    
84.             $this->query_num++;    
85.                 return $this->rs;    
86.             }    
87.         }    
88.   
89.         public function getOne($sql) {    
90.             $this->query($sql, 1);    
91.             $this->fetch_mode    = MYSQLI_NUM;    
92.             $row = $this->fetch();    
93.             $this->free();    
94.             return $row[0];    
95.         }    
96.   
97.         public function get_one($sql) {    
98.             return $this->getOne($sql);    
99.         }    
100.   
101.         public function cache_one($sql) {    
102.             $sql    = $this->getQuerySql($sql, 1);    
103.             return $this->get_cache($sql, 'getOne');    
104.         }    
105.   
106.         public function getRow($sql, $fetch_mode = MYSQLI_ASSOC) {    
107.             $this->query($sql, 1);    
108.             $this->fetch_mode    = $fetch_mode;    
109.             $row = $this->fetch();    
110.             $this->free();    
111.             return $row;    
112.         }    
113.   
114.         public function get_row($sql, $fetch_mode = MYSQLI_ASSOC) {    
115.             return $this->getRow($sql);   
116.         }    
117.   
118.         public function cache_row($sql) {    
119.             $sql    = $this->getQuerySql($sql, 1);    
120.             return $this->get_cache($sql, 'getRow');    
121.         }    
122.   
123.         public function getAll($sql, $limit = null, $fetch_mode = MYSQLI_ASSOC) {    
124.             $this->query($sql, $limit);    
125.             $all_rows = array();    
126.             $this->fetch_mode    = $fetch_mode;    
127.             while($rows = $this->fetch()) {    
128.                 $all_rows[] = $rows;    
129.             }    
130.             $this->free();    
131.             return $all_rows;    
132.         }    
133.         public function get_all($sql, $limit = null, $fetch_mode = MYSQLI_ASSOC) {    
134.             return $this->getAll($sql);    
135.         }    
136.   
137.         public function cache_all($sql, $limit = null) {    
138.             $sql    = $this->getQuerySql($sql, $limit);    
139.             return $this->get_cache($sql, 'getAll');    
140.         }    
141.   
142.         public function insert_id() {    
143.             return $this->mysqli->insert_id();    
144.         }    
145.   
146.         public function escape($str) {    
147.             if(is_array($str)) {    
148.                 foreach($str as $key=>$val) {    
149.                     $str[$key] = $this->escape($val);    
150.                 }    
151.             } else {    
152.                 $str = addslashes(trim($str));    
153.             }   //开源代码Vevb.com 
154.             return $str;    
155.         }    
156.     }    
157.     //用法    
158.     $db    = new db_mysqli('localhost', 'root', 111222, 'dict');    
159.     $db->set_cache_time(10);    
160.     $db->set_cache_dir('./cache/sql/');    
161.     $sql = "select * from words order by word_id limit 10,10";    
162.     $res1 = $db->get_all($sql);    
163.     $res2 = $db->cache_all($sql);    
164.   
165.     echo $db->query_num(),'<br>';    
166.     ?>