<?php                        // 配置数据库      define('DB_HOST', '127.0.0.1');   //服务器地址    define('DB_USER', 'root');   //用户名    define('DB_PASS', '');  //密码    define('DB_DATABASENAME', 'fenxiao'); //数据库                      class Dbmysql    {             /*    *变量    **/    private $tablename=""; //表名    private $fieldname="*";    private $conn;    private $where;    private $sql;          function __construct($tablename)    {    //生成一个连接    $this->conn = mysql_connect(DB_HOST, DB_USER, DB_PASS) or die("connect failed" . mysql_error());      //选择数据库    mysql_select_db(DB_DATABASENAME, $this->conn);     //设置编码格式    mysql_query("SET NAMES utf8");    //var_dump($conn);    $this->tablename=$tablename;    }          //设置sql语句    private function setsql($sql)    {    $this->sql=$sql;    }          //设置条件语句    public function where($where)    {    $this->where=" where ".$where;          return $this;    }          //按指定字段    public function field($keyword)    {    $this->fieldname=$keyword;    return $this;    }    //设置连接查询表    public function table($table1,$table2,$field,$bool)    {    $this->tablename="$table1 LEFT JOIN $table2 ON $table1.$field$bool$table2.$field";    //print_r($this->tablename);    return $this;    }      //设置多表查询    public function addtable($table1,$table2,$field,$bool)    {    $this->tablename.=" LEFT JOIN $table2 ON $table1.$field$bool$table2.$field";    //print_r($this->tablename);    return $this;    }          //设置连接查询表    ##SELECT * FROM 【wx_order LEFT JOIN wx_shopcar ON wx_shopcar.oid=wx_order.oid and wx_order.uid=wx_shopcar.uid LEFT JOIN wx_goods ON wx_shopcar.gid=wx_goods.gid】 WHERE wx_order.oid=1 and wx_order.uid=3    public function settable($sql)    {    $this->tablename=$sql;    //print_r($this->tablename);    return $this;    }          //查询所有数据库 以数组形式输出    public function select()    {      /**    * 查询数据库中所有的数据    **/    $arr=array();    //执行sql语句    $result = mysql_query("select ".$this->fieldname." from ".$this->tablename.$this->where, $this->conn);           while ($row = mysql_fetch_assoc($result)) {      array_push($arr, $row);    }          return $arr;     }          //搜索指定字段数据    public function find()    {    //执行sql语句    $result = mysql_query("select ".$this->fieldname." from ".$this->tablename.$this->where, $this->conn);     $result = mysql_fetch_assoc($result);    return $result;    }          //增加数据到数据库    public function add($data)    {    $keysql='';    $valuesql='';    foreach ($data as $key => $value) {    $keysql.=",`$key`";    $valuesql.=",'$value'";    }    $keysql=substr($keysql, 1);    $valuesql=substr($valuesql, 1);    $result=mysql_query("insert into `".$this->tablename."` ($keysql) VALUES($valuesql)");    $id=mysql_insert_id();    //print_r("insert into `".$this->tablename."` ($keysql) VALUES($valuesql)");    return $id;    }          //修改数据库的内容    public function save($data)    {    $keysql='';    $valuesql='';    foreach ($data as $key => $value) {    $keysql.=",`$key`='$value'";    }    $keysql=substr($keysql, 1);    //print_r($keysql);    //echo "<br>";    $result=mysql_query("UPDATE `".$this->tablename."` SET ".$keysql.$this->where);    //print_r("UPDATE `".$this->tablename."` SET ".$keysql.$this->where);    return $result;    }          ##删除数据    public function delete()    {    $result=mysql_query("DELETE FROM $this->tablename $this->where");    //print_r("DELETE FROM $this->tablename $this->where");    return $result;    }          }          /**    * mysql_fetch_row: 返回单列的各字段 [0]=>"111"    * mysql_fetch_field: 取得字段信息。[0]=>   ['name']=>   object    * mysql_fetch_array    返回数组资料。 [0]=>"asasds"   ['name']=>    */    ?>

来自： http://my.oschina.net/Peron/blog/552601