PHP数据库操作基类(单例模式)

自己练习写的数据库操作基类,包含最基本的CURD操作.可集成到框架内.

1. // 配置文件
2. $db = array(
3. 'host'=>'localhost',
4. 'user'=>'root',
5. 'password'=>'',
6. 'database'=>'test',
7. )
9. ?>
10. //php 类
11. class db {
12. public $conn;
13. public static $sql;
14. public static $instance=null;
15. private function __construct(){
16. require_once('db.config.php');
17. $this->conn = mysql_connect($db['host'],$db['user'],$db['password']);
18. if(!mysql_select_db($db['database'],$this->conn)){
19. echo "失败";
20. };
21. mysql_query('set names utf8',$this->conn);
22. }
23. public static function getInstance(){
24. if(is_null(self::$instance)){
25. self::$instance = new db;
26. }
27. return self::$instance;
28. }
29. /**
30. * 查询数据库
31. */
32. public function select($table,$condition=array(),$field = array()){
33. $where='';
34. if(!empty($condition)){
36. foreach($condition as $k=>$v){
37. $where.=$k."='".$v."' and ";
38. }
39. $where='where '.$where .'1=1';
40. }
41. $fieldstr = '';
42. if(!empty($field)){
44. foreach($field as $k=>$v){
45. $fieldstr.= $v.',';
46. }
47. $fieldstr = rtrim($fieldstr,',');
48. }else{
49. $fieldstr = '*';
50. }
51. self::$sql = "select {$fieldstr} from {$table} {$where}";
52. $result=mysql_query(self::$sql,$this->conn);
53. $resuleRow = array();
54. $i = 0;
55. while($row=mysql_fetch_assoc($result)){
56. foreach($row as $k=>$v){
57. $resuleRow[$i][$k] = $v;
58. }
59. $i++;
60. }
61. return $resuleRow;
62. }
63. /**
64. * 添加一条记录
65. */
66. public function insert($table,$data){
67. $values = '';
68. $datas = '';
69. foreach($data as $k=>$v){
70. $values.=$k.',';
71. $datas.="'$v'".',';
72. }
73. $values = rtrim($values,',');
74. $datas = rtrim($datas,',');
75. self::$sql = "INSERT INTO {$table} ({$values}) VALUES ({$datas})";
76. if(mysql_query(self::$sql)){
77. return mysql_insert_id();
78. }else{
79. return false;
80. };
81. }
82. /**
83. * 修改一条记录
84. */
85. public function update($table,$data,$condition=array()){
86. $where='';
87. if(!empty($condition)){
89. foreach($condition as $k=>$v){
90. $where.=$k."='".$v."' and ";
91. }
92. $where='where '.$where .'1=1';
93. }
94. $updatastr = '';
95. if(!empty($data)){
96. foreach($data as $k=>$v){
97. $updatastr.= $k."='".$v."',";
98. }
99. $updatastr = 'set '.rtrim($updatastr,',');
100. }
101. self::$sql = "update {$table} {$updatastr} {$where}";
102. return mysql_query(self::$sql);
103. }
104. /**
105. * 删除记录
106. */
107. public function delete($table,$condition){
108. $where='';
109. if(!empty($condition)){
111. foreach($condition as $k=>$v){
112. $where.=$k."='".$v."' and ";
113. }
114. $where='where '.$where .'1=1';
115. }
116. self::$sql = "delete from {$table} {$where}";
117. return mysql_query(self::$sql);
119. }
121. public static function getLastSql(){
122. echo self::$sql;
123. }
127. }

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

复制代码

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

     ";

126. ?>

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