这篇文章主要介绍了PHP基于单例模式实现的数据库操作基类,涉及PHP操作数据库的基本配置与增删改查等操作技巧,需要的朋友可以参考下。

本文实例讲述了PHP基于单例模式实现的数据库操作基类，分享给大家供大家参考，具体如下：

配置文件：

1. <?php
2. $db = array(
3. 'host'=>'localhost',
4. 'user'=>'root',
5. 'password'=>'',
6. 'database'=>'test',
7. )
8. ?>

php 数据库基类：

1. <?php
2. class db {
3. public $conn;
4. public static $sql;
5. public static $instance=null;
6. private function __construct(){
7. require_once('db.config.php');
8. $this->conn = mysql_connect($db['host'],$db['user'],$db['password']);
9. if(!mysql_select_db($db['database'],$this->conn)){
10. echo "失败";
11. };
12. mysql_query('set names utf8',$this->conn);
13. }
14. public static function getInstance(){
15. if(is_null(self::$instance)){
16. self::$instance = new db;
17. }
18. return self::$instance;
19. }
20. /**
21. * 查询数据库
22. */
23. public function select($table,$condition=array(),$field = array()){
24. $where='';
25. if(!emptyempty($condition)){
26. foreach($condition as $k=>$v){
27. $where.=$k."='".$v."' and ";
28. }
29. $where='where '.$where .'1=1';
30. }
31. $fieldstr = '';
32. if(!emptyempty($field)){
33. foreach($field as $k=>$v){
34. $fieldstr.= $v.',';
35. }
36. $fieldstr = rtrim($fieldstr,',');
37. }else{
38. $fieldstr = '*';
39. }
40. self::$sql = "select {$fieldstr} from {$table} {$where}";
41. $result=mysql_query(self::$sql,$this->conn);
42. $resuleRow = array();
43. $i = 0;
44. while($row=mysql_fetch_assoc($result)){
45. foreach($row as $k=>$v){
46. $resuleRow[$i][$k] = $v;
47. }
48. $i++;
49. }
50. return $resuleRow;
51. }
52. /**
53. * 添加一条记录
54. */
55. public function insert($table,$data){
56. $values = '';
57. $datas = '';
58. foreach($data as $k=>$v){
59. $values.=$k.',';
60. $datas.="'$v'".',';
61. }
62. $values = rtrim($values,',');
63. $datas = rtrim($datas,',');
64. self::$sql = "INSERT INTO {$table} ({$values}) VALUES ({$datas})";
65. if(mysql_query(self::$sql)){
66. return mysql_insert_id();
67. }else{
68. return false;
69. };
70. }
71. /**
72. * 修改一条记录
73. */
74. public function update($table,$data,$condition=array()){
75. $where='';
76. if(!emptyempty($condition)){
77. foreach($condition as $k=>$v){
78. $where.=$k."='".$v."' and ";
79. }
80. $where='where '.$where .'1=1';
81. }
82. $updatastr = '';
83. if(!emptyempty($data)){
84. foreach($data as $k=>$v){
85. $updatastr.= $k."='".$v."',";
86. }
87. $updatastr = 'set '.rtrim($updatastr,',');
88. }
89. self::$sql = "update {$table} {$updatastr} {$where}";
90. return mysql_query(self::$sql);
91. }
92. /**
93. * 删除记录
94. */
95. public function delete($table,$condition){
96. $where='';
97. if(!emptyempty($condition)){
98. foreach($condition as $k=>$v){
99. $where.=$k."='".$v."' and ";
100. }
101. $where='where '.$where .'1=1';
102. }
103. self::$sql = "delete from {$table} {$where}";
104. return mysql_query(self::$sql);
105. }
106. public static function getLastSql(){
107. echo self::$sql;
108. }
109. }
110. $db = db::getInstance();
111. //$list = $db->select('demo',array('name'=>'tom','password'=>'ds'),array('name','password'));
112. //echo $db->insert('demo',array('name'=>'脚本之家','password'=>'123'));
113. //echo $db->update('demo',array("name"=>'xxx',"password"=>'123'),array('id'=>1));
114. echo $db->delete('demo',array('id'=>'2'));
115. db::getLastSql();
116. echo "<pre>";
117. ?>