本文所述的是一个在PHP中以mysqli方式连接数据库的一个数据库类实例，该数据库类是从一个PHP的CMS中整理出来的，可实现PHP连接数据库类，MySQLi版，兼容PHP4，对于有针对性需要的朋友可根据此代码进行优化和修改。
<?php
#==================================================================================================
# Filename: /db/db_mysqli.php
# Note : 连接数据库类，MySQLi版
#==================================================================================================
#[类库sql]
class db_mysqli
{
var $query_count = 0;
var $host;
var $user;
var $pass;
var $data;
var $conn;
var $result;
var $prefix = "qinggan_";
//返回结果集类型，默认是数字+字符
var $rs_type = MYSQLI_ASSOC;
var $query_times = 0;#[查询时间]
var $conn_times = 0;#[连接数据库时间]
var $unbuffered = false;
//定义查询列表
var $querylist;
var $debug = false;
#[构造函数]
function __construct($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'] : '';
$this->data = $config['data'] ? $config['data'] : '';
$this->debug = $config["debug"] ? $config["debug"] : false;
$this->prefix = $config['prefix'] ? $config['prefix'] : 'qinggan_';
if($this->data)
{
$ifconnect = $this->connect($this->data);
if(!$ifconnect)
{
$this->conn = false;
return false;
}
}
return true;
}
#[兼容PHP4]
function db_mysqli($config=array())
{
return $this->__construct($config);
}
#[连接数据库]
function connect($database="")
{
$start_time = $this->time_used();
if(!$this->port) $this->port = "3306";
$this->conn = @mysqli_connect($this->host,$this->user,$this->pass,"",$this->port) or false;
if(!$this->conn)
{
return false;
}
$version = $this->get_version();
if($version>"4.1")
{
mysqli_query($this->conn,"SET NAMES 'utf8'");
if($version>"5.0.1")
{
mysqli_query($this->conn,"SET sql_mode=''");
}
}
$end_time = $this->time_used();
$this->conn_times += round($end_time - $start_time,5);#[连接数据库的时间]
$ifok = $this->select_db($database);
return $ifok ? true : false;
}
function select_db($data="")
{
$database = $data ? $data : $this->data;
if(!$database)
{
return false;
}
$this->data = $database;
$start_time = $this->time_used();
$ifok = mysqli_select_db($this->conn,$database);
if(!$ifok)
{
return false;
}
$end_time = $this->time_used();
$this->conn_times += round($end_time - $start_time,5);#[连接数据库的时间]
return true;
}
#[关闭数据库连接，当您使用持续连接时该功能失效]
function close()
{
if(is_resource($this->conn))
{
return mysqli_close($this->conn);
}
else
{
return true;
}
}
function __destruct()
{
return $this->close();
}
function set($name,$value)
{
if($name == "rs_type")
{
$value = strtolower($value) == "num" ? MYSQLI_NUM : MYSQLI_ASSOC;
}
$this->$name = $value;
}
function query($sql)
{
if(!is_resource($this->conn))
{
$this->connect();
}
else
{
if(!mysql_ping($this->conn))
{
$this->close();
$this->connect();
}
}
if($this->debug)
{
$sqlkey = md5($sql);
if($this->querylist)
{
$qlist = array_keys($this->querylist);
if(in_array($sqlkey,$qlist))
{
$count = $this->querylist[$sqlkey]["count"] + 1;
$this->querylist[$sqlkey] = array("sql"=>$sql,"count"=>$count);
}else{
$this->querylist[$sqlkey] = array("sql"=>$sql,"count"=>1);
}
}
else{
$this->querylist[$sqlkey] = array("sql"=>$sql,"count"=>1);
}
}
$start_time = $this->time_used();
$func = $this->unbuffered && function_exists("mysqli_multi_query") ? "mysqli_multi_query" : "mysqli_query";
$this->result = @$func($this->conn,$sql);
$this->query_count++;
$end_time = $this->time_used();
$this->query_times += round($end_time - $start_time,5);#[查询时间]
if(!$this->result)
{
return false;
}
return $this->result;
}
function get_all($sql="",$primary="")
{
$result = $sql ? $this->query($sql) : $this->result;
if(!$result)
{
return false;
}
$start_time = $this->time_used();
$rs = array();
$is_rs = false;
while($rows = mysqli_fetch_array($result,$this->rs_type))
{
if($primary && $rows[$primary])
{
$rs[$rows[$primary]] = $rows;
}
else
{
$rs[] = $rows;
}
$is_rs = true;
}
$end_time = $this->time_used();
$this->query_times += round($end_time - $start_time,5);#[查询时间]
return ($is_rs ? $rs : false);
}
function get_one($sql="")
{
$start_time = $this->time_used();
$result = $sql ? $this->query($sql) : $this->result;
if(!$result)
{
return false;
}
$rows = mysqli_fetch_array($result,$this->rs_type);
$end_time = $this->time_used();
$this->query_times += round($end_time - $start_time,5);#[查询时间]
return $rows;
}
function insert_id($sql="")
{
if($sql)
{
$rs = $this->get_one($sql);
return $rs;
}
else
{
return mysqli_insert_id($this->conn);
}
}
function insert($sql)
{
$this->result = $this->query($sql);
$id = $this->insert_id();
return $id;
}
function all_array($table,$condition="",$orderby="")
{
if(!$table)
{
return false;
}
$table = $this->prefix.$table;
$sql = "SELECT * FROM ".$table;
if($condition && is_array($condition) && count($condition)>0)
{
$sql_fields = array();
foreach($condition AS $key=>$value)
{
$sql_fields[] = "`".$key."`='".$value."' ";
}
$sql .= " WHERE ".implode(" AND ",$sql_fields);
}
if($orderby)
{
$sql .= " ORDER BY ".$orderby;
}
$rslist = $this->get_all($sql);
return $rslist;
}
function one_array($table,$condition="")
{
if(!$table)
{
return false;
}
$table = $this->prefix.$table;
$sql = "SELECT * FROM ".$table;
if($condition && is_array($condition) && count($condition)>0)
{
$sql_fields = array();
foreach($condition AS $key=>$value)
{
$sql_fields[] = "`".$key."`='".$value."' ";
}
$sql .= " WHERE ".implode(" AND ",$sql_fields);
}
$rslist = $this->get_one($sql);
return $rslist;
}
//将数组写入数据中
function insert_array($data,$table,$insert_type="insert")
{
if(!$table || !is_array($data) || !$data)
{
return false;
}
$table = $this->prefix.$table;//自动增加表前缀
if($insert_type == "insert")
{
$sql = "INSERT INTO ".$table;
}
else
{
$sql = "REPLACE INTO ".$table;
}
$sql_fields = array();
$sql_val = array();
foreach($data AS $key=>$value)
{
$sql_fields[] = "`".$key."`";
$sql_val[] = "'".$value."'";
}
$sql.= "(".(implode(",",$sql_fields)).") VALUES(".(implode(",",$sql_val)).")";
return $this->insert($sql);
}
//更新数据
function update_array($data,$table,$condition)
{
if(!$data || !$table || !$condition || !is_array($data) || !is_array($condition))
{
return false;
}
$table = $this->prefix.$table;//自动增加表前缀
$sql = "UPDATE ".$table." SET ";
$sql_fields = array();
foreach($data AS $key=>$value)
{
$sql_fields[] = "`".$key."`='".$value."'";
}
$sql.= implode(",",$sql_fields);
$sql_fields = array();
foreach($condition AS $key=>$value)
{
$sql_fields[] = "`".$key."`='".$value."' ";
}
$sql .= " WHERE ".implode(" AND ",$sql_fields);
return $this->query($sql);
}
function count($sql="")
{
if($sql)
{
$this->rs_type = MYSQLI_NUM;
$this->query($sql);
$rs = $this->get_one();
$this->rs_type = MYSQLI_ASSOC;
return $rs[0];
}
else
{
return mysqli_num_rows($this->result);
}
}
function num_fields($sql="")
{
if($sql)
{
$this->query($sql);
}
return mysqli_num_fields($this->result);
}
function list_fields($table)
{
$rs = $this->get_all("SHOW COLUMNS FROM ".$table);
if(!$rs)
{
return false;
}
foreach($rs AS $key=>$value)
{
$rslist[] = $value["Field"];
}
return $rslist;
}
#[显示表名]
function list_tables()
{
$rs = $this->get_all("SHOW TABLES");
return $rs;
}
function table_name($table_list,$i)
{
return $table_list[$i];
}
function escape_string($char)
{
if(!$char)
{
return false;
}
return mysqli_escape_string($this->conn,$char);
}
function get_version()
{
return mysqli_get_server_info($this->conn);
}
function time_used()
{
$time = explode(" ",microtime());
$used_time = $time[0] + $time[1];
return $used_time;
}
//Mysql的查询时间
function conn_times()
{
return $this->conn_times + $this->query_times;
}
//MySQL查询资料
function conn_count()
{
return $this->query_count;
}
# 高效SQL生成查询，仅适合单表查询
function phpok_one($tbl,$condition="",$fields="*")
{
$sql = "SELECT ".$fields." FROM ".$this->db->prefix.$tbl;
if($condition)
{
$sql .= " WHERE ".$condition;
}
return $this->get_one($sql);
}
function debug()
{
if(!$this->querylist || !is_array($this->querylist) || count($this->querylist) < 1)
{
return false;
}
$html = '<table cellpadding="0" cellspacing="0" width="100%" bgcolor="#CECECE"><tr><td>';
$html.= '<table cellpadding="1" cellspacing="1" width="100%">';
$html.= '<tr><th bgcolor="#EFEFEF" height="30px">SQL</th><th bgcolor="#EFEFEF" width="80px">查询</th></tr>';
foreach($this->querylist AS $key=>$value)
{
$html .= '<tr><td bgcolor="#FFFFFF"><div style="padding:3px;color:#6E6E6E;">'.$value['sql'].'</div></td>';
$html .= '<td align="center" bgcolor="#FFFFFF"><div style="padding:3px;color:#000000;">'.$value["count"].'</div></td></tr>';
}
$html.= "</table>";
$html.= "</td></tr></table>";
return $html;
}
function conn_status()
{
if(!$this->conn) return false;
return true;
}
}
?>