<?php
namespace apijson;

use PDO;

class Db
{
 //连接PDO实例
 public static $con = null;
 //数据库所有表
 public static $tables;
 //当前操作的表
 public $table;
 public $field = "*";
 public $key = [];
 public $logic = [];
 public $val = [];
 private $PDOStatement;

 public function __construct()
 {
 }
 /**
 * connect
 */
 public static function connect($server, $database, $name, $pwd, $port = 3306)
 {
 if (!self::$con) {
 try {
 self::$con = new PDO("mysql:host={$server};dbname={$database}", $name, $pwd);
 self::$tables = self::$con->query("show tables")->fetchAll(PDO::FETCH_COLUMN);
 } catch (PDOException $e) {
 die($e->getMessage());
 }
 }
 }
 /**
 * exe main
 */
 public function exe($request)
 {
 var_dump($request);
 }
 /**
 * table
 */
 public function table($table)
 {
 $this->table = $table;
 return $this;
 }
 /**
 * field
 */
 public function field($field)
 {
 $this->field = $field;
 return $this;
 }
 /**
 * where
 */
 public function where($where = [])
 {
 $count = func_num_args();
 if ($count == 1) {
 if (is_array($where)) {
 foreach ($where as $k => $v) {
 $this->key[] = $k;
 if (is_array($v)) {

 } else {
 $this->logic[] = '=';
 $this->val[] = $v;
 }
 }
 }
 }
 }
 /**
 * query
 */
 public function query($sql)
 {
 $this->PDOStatement = self::$con->prepare($sql);
 $this->PDOStatement->execute();
 return $this->PDOStatement->fetchAll(PDO::FETCH_ASSOC);
 }
 /**
 * get
 */
 public function get()
 {

 }
}