基于mysqli封装的数据库类

忘是亡心i 2023-10-17 15:08 138阅读 0赞

本文实例讲述了php封装的mysqli类。分享给大家供大家参考，具体如下： 
类： 
<?php 
header('content-type:text/html;charset=utf-8'); 
/\* 
掌握满足单例模式的必要条件 
(1)私有的构造方法-为了防止在类外使用new关键字实例化对象 
(2)私有的成员属性-为了防止在类外引入这个存放对象的属性 
(3)私有的克隆方法-为了防止在类外通过clone成生另一个对象 
(4)公有的静态方法-为了让用户进行实例化对象的操作 
\*/ 
class ConnectMysqli\{ 
//私有的属性 
private static $dbcon=false; 
private $host; 
private $port; 
private $user; 
private $pass; 
private $db; 
private $charset; 
private $link; 
//私有的构造方法 
private function \_\_construct($config=array())\{ 
$this->host = $config\['host'\] ? $config\['host'\] : 'localhost'; 
$this->port = $config\['port'\] ? $config\['port'\] : '3306'; 
$this->user = $config\['user'\] ? $config\['user'\] : 'root'; 
$this->pass = $config\['pass'\] ? $config\['pass'\] : 'root'; 
$this->db = $config\['db'\] ? $config\['db'\] : 'small2'; 
$this->charset=isset($arr\['charset'\]) ? $arr\['charset'\] : 'utf8'; 
//连接数据库 
$this->db\_connect(); 
//选择数据库 
$this->db\_usedb(); 
//设置字符集 
$this->db\_charset(); 
\} 
//连接数据库 
private function db\_connect()\{ 
$this->link=mysqli\_connect($this->host.':'.$this->port,$this->user,$this->pass); 
if(!$this->link)\{ 
echo "数据库连接失败 "; 
echo "错误编码".mysqli\_errno($this->link)." "; 
echo "错误信息".mysqli\_error($this->link)." "; 
exit; 
\} 
\} 
//设置字符集 
private function db\_charset()\{ 
mysqli\_query($this->link,"set names \{$this->charset\}"); 
\} 
//选择数据库 
private function db\_usedb()\{ 
mysqli\_query($this->link,"use \{$this->db\}"); 
\} 
//私有的克隆 
private function \_\_clone()\{ 
die('clone is not allowed'); 
\} 
//公用的静态方法 
public static function getIntance()\{ 
if(self::$dbcon==false)\{ 
self::$dbcon=new self; 
\} 
return self::$dbcon; 
\} 
//执行sql语句的方法 
public function query($sql)\{ 
$res=mysqli\_query($this->link,$sql); 
if(!$res)\{ 
echo "sql语句执行失败 "; 
echo "错误编码是".mysqli\_errno($this->link)." "; 
echo "错误信息是".mysqli\_error($this->link)." "; 
\} 
return $res; 
\} 
//打印数据 
public function p($arr)\{ 
echo "<pre>"; 
print\_r($arr); 
echo "</pre>"; 
\} 
public function v($arr)\{ 
echo "<pre>"; 
var\_dump($arr); 
echo "</pre>"; 
\} 
//获得最后一条记录id 
public function getInsertid()\{ 
return mysqli\_insert\_id($this->link); 
\} 
/\*\* 
\* 查询某个字段 
\* @param 
\* @return string or int 
\*/ 
public function getOne($sql)\{ 
$query=$this->query($sql); 
return mysqli\_free\_result($query); 
\} 
//获取一行记录,return array 一维数组 
public function getRow($sql,$type="assoc")\{ 
$query=$this->query($sql); 
if(!in\_array($type,array("assoc",'array',"row")))\{ 
die("mysqli\_query error"); 
\} 
$funcname="mysqli\_fetch\_".$type; 
return $funcname($query); 
\} 
//获取一条记录,前置条件通过资源获取一条记录 
public function getFormSource($query,$type="assoc")\{ 
if(!in\_array($type,array("assoc","array","row"))) 
\{ 
die("mysqli\_query error"); 
\} 
$funcname="mysqli\_fetch\_".$type; 
return $funcname($query); 
\} 
//获取多条数据，二维数组 
public function getAll($sql)\{ 
$query=$this->query($sql); 
$list=array(); 
while ($r=$this->getFormSource($query)) \{ 
$list\[\]=$r; 
\} 
return $list; 
\} 
/\*\* 
\* 定义添加数据的方法 
\* @param string $table 表名 
\* @param string orarray $data \[数据\] 
\* @return int 最新添加的id 
\*/ 
public function insert($table,$data)\{ 
//遍历数组，得到每一个字段和字段的值 
$key\_str=''; 
$v\_str=''; 
foreach($data as $key=>$v)\{ 
if(empty($v))\{ 
die("error"); 
\} 
//$key的值是每一个字段s一个字段所对应的值 
$key\_str.=$key.','; 
$v\_str.="'$v',"; 
\} 
$key\_str=trim($key\_str,','); 
$v\_str=trim($v\_str,','); 
//判断数据是否为空 
$sql="insert into $table ($key\_str) values ($v\_str)"; 
$this->query($sql); 
//返回上一次增加操做产生ID值 
return $this->getInsertid(); 
\} 
/\* 
\* 删除一条数据方法 
\* @param1 $table, $where=array('id'=>'1') 表名 条件 
\* @return 受影响的行数 
\*/ 
public function deleteOne($table, $where)\{ 
if(is\_array($where))\{ 
foreach ($where as $key => $val) \{ 
$condition = $key.'='.$val; 
\} 
\} else \{ 
$condition = $where; 
\} 
$sql = "delete from $table where $condition"; 
$this->query($sql); 
//返回受影响的行数 
return mysqli\_affected\_rows($this->link); 
\} 
/\* 
\* 删除多条数据方法 
\* @param1 $table, $where 表名 条件 
\* @return 受影响的行数 
\*/ 
public function deleteAll($table, $where)\{ 
if(is\_array($where))\{ 
foreach ($where as $key => $val) \{ 
if(is\_array($val))\{ 
$condition = $key.' in ('.implode(',', $val) .')'; 
\} else \{ 
$condition = $key. '=' .$val; 
\} 
\} 
\} else \{ 
$condition = $where; 
\} 
$sql = "delete from $table where $condition"; 
$this->query($sql); 
//返回受影响的行数 
return mysqli\_affected\_rows($this->link); 
\} 
/\*\* 
\* \[修改操作description\] 
\* @param \[type\] $table \[表名\] 
\* @param \[type\] $data \[数据\] 
\* @param \[type\] $where \[条件\] 
\* @return \[type\] 
\*/ 
public function update($table,$data,$where)\{ 
//遍历数组，得到每一个字段和字段的值 
$str=''; 
foreach($data as $key=>$v)\{ 
$str.="$key='$v',"; 
\} 
$str=rtrim($str,','); 
//修改SQL语句 
$sql="update $table set $str where $where"; 
$this->query($sql); 
//返回受影响的行数 
return mysqli\_affected\_rows($this->link); 
\} 
\} 
?> 
 
用法测试： 
//mysqli测试 
$db=ConnectMysqli::getIntance(); 
//var\_dump($db); 
/\*$sql="select \* from acticle"; 
$list=$db->getAll($sql); 
$db->p($list);\*/ 
/\*$sql="select \* from acticle where acticle\_id=95"; 
$list=$db->getRow($sql); 
$db->p($list); 
\*/ 
/\*$sql="select title from acticle"; 
$list=$db->getOne($sql); 
$db->p($list);不行\*/ 
//$list=$db->insert("users",$\_POST); 
//$del=$db->deleteOne("users","id=29"); 
//$del=$db->deleteAll("users","id in(27,28)"); 
//$up=$db->update("users",$\_POST,"id=27"); 
//print\_R($list);

来源:http://www.thinkphp.cn/topic/50610.html