PHPmysqli数据库操作类

<!--?php
class Mysql{
private $host = 'localhost';
private $port = '3306';
private $user = 'username';
private $pwd = 'password';
private $db = 'dbname';
private $char = 'UTF8';
private $prefix = '';
private $fetch_mode = MYSQLI_ASSOC;//获取模式
private $result;//结果集
public $mysqli;//mysqli实例<strong-->对象
static private $_instance;//本类实例
//构造函数初始化$mysqli<strong>对象</strong>
private function __construct() {
$this->mysqli=new mysqli($this->host,$this->user,$this->pwd,$this->db,$this->port);
if(mysqli_connect_errno()){
$this->mysqli=false;
echo mysqli_connect_error();
die();
}else{
$this->mysqli->set_charset($char);
}
}
//析构函数：释放结果集和关闭数据库
public function __destruct(){
$this->free();
$this->close();
}
//初始化$mysqli<strong>对象</strong>
public static function getInstance(){
if(!(self::$_instance instanceof self)) {
self::$_instance = new self();
}
return self::$_instance;
}
//释放结果集
private function free(){
@$this->result->free();
}
//关闭数据库连接
private function close(){
$this->mysqli->close();
}
//执行sql语句
public function query($sql){
return $this->mysqli->query($sql);
}
//获取查询结果
public function get_result_array($table,$field,$c
$table=$this->prefix.$table;
if(is_array($field)){
$field = join(',',$field);
}
$sql = "SELECT $field FROM ".$table;
if(!empty($condition))$sql .=" $condition ";
$this->result = $this->query($sql);
$return = array();
while($row = $this->fetch($this->result)){
$return[] = $row;
}
$this->free();
return $return;
}
//增删改操作
public function execute($table,$action,$arr_field=array(),$c
$table=$this->prefix.$table;
switch($action){
case 'INSERT':
$str_field = '';
$str_val = '';
foreach($arr_field as $key=>$val){
$str_field .= '`'.$key.'`,';
$str_val .= '\''.$val.'\',';
}
$str_field = rtrim($str_field, ',');
$str_val = rtrim($str_val, ',');
$sql = "INSERT INTO $table ($str_field) VALUES ($str_val) ";
break;
case 'DELETE':
$sql = "DELETE FROM $table";
if (!empty($condition)) $sql .= " WHERE $condition";
break;
case 'UPDATE':
$str_field = '';
foreach($arr_field as $key => $val){
$str_field.= '`'.$key ."` ='$val',";
}
$str_field = rtrim($str_field, ',');
$sql = "UPDATE $table SET $str_field";
if (!empty($condition)) $sql .= " WHERE $condition";
break;
}
$this->query($sql);
return $this->get_affected_rows();
}
//获得受影响行数(针对增删改操作)
public function get_affected_rows(){
return $this->mysqli->affected_rows;
}
//获取集合条数
public function get_rows($table,$c 1 ',$id='id'){
$table=$this->prefix.$table;
$sql="SELECT COUNT($id) num FROM ".$table." $condition";
$this->result=$this->query($sql);
$row=$this->fetch($this->result);
return $row['num'];
}
//获得结果集
public function fetch($result){
return $result->fetch_array($this->fetch_mode);
}
//获得所有结果集
public function fetch_all($result){
$rows=array();
while($row=$this->fetch($result)){
$rows[]=$row;
}
return $rows;
}
}

以上就介绍了PHP mysqli数据库操作类，包括了对象方面的内容，希望对PHP教程有兴趣的朋友有所帮助。