<?php
//一个普遍通用的PHP连接MYSQL数据库类
class mysql {
    private $db_host; //数据库主机
    private $db_user; //数据库用户名
    private $db_pwd; //数据库用户名密码
    private $db_database; //数据库名
    private $conn; //数据库连接标识;
    private $result; //执行query命令的结果资源标识
    private $sql; //sql执行语句
    private $row; //返回的条目数
    private $coding; //数据库编码，GBK,UTF8,gb2312
    private $bulletin = true; //是否开启错误记录
    private $show_error = true; //测试阶段，显示所有错误,具有安全隐患,默认关闭
    private $is_error = false; //发现错误是否立即终止,默认true,建议不启用，因为当有问题时用户什么也看不到是很苦恼的

    
    public function __construct($db_host, $db_user, $db_pwd, $db_database, $conn, $coding) {
        $this->db_host = $db_host;
        $this->db_user = $db_user;
        $this->db_pwd = $db_pwd;
        $this->db_database = $db_database;
        $this->conn = $conn;
        $this->coding = $coding;
        $this->connect();
    }

    
    public function connect() {
        if ($this->conn == "pconn") {
            //永久链接
            $this->conn = mysql_pconnect($this->db_host, $this->db_user, $this->db_pwd);
        } else {
            //即使链接
            $this->conn = mysql_connect($this->db_host, $this->db_user, $this->db_pwd);
        }

        if (!mysql_select_db($this->db_database, $this->conn)) {
            if ($this->show_error) {
                $this->show_error("数据库不可用：", $this->db_database);
            }
        }
        mysql_query("SET NAMES $this->coding");
    }
     
    
    public function query($sql) {
        if ($sql == "") {
            $this->show_error("SQL语句错误：", "SQL查询语句为空");
        }
        $this->sql = $sql;

        $result = mysql_query($this->sql, $this->conn);

        if (!$result) {
            //调试中使用，sql语句出错时会自动打印出来
            if ($this->show_error) {
                $this->show_error("错误SQL语句：", $this->sql);
            }
        } else {
            $this->result = $result;
        }
        return $this->result;
    }

    
    public function create_database($database_name) {
        $database = $database_name;
        $sqlDatabase = 'create database ' . $database;
        $this->query($sqlDatabase);
    }

    
    //将系统数据库与用户数据库分开，更直观的显示？
    public function show_databases() {
        $this->query("show databases");
        echo "现有数据库：" . $amount = $this->db_num_rows($rs);
        echo "<br />";
        $i = 1;
        while ($row = $this->fetch_array($rs)) {
            echo "$i $row[Database]";
            echo "<br />";
            $i++;
        }
    }

    //以数组形式返回主机中所有数据库名
    public function databases() {
        $rsPtr = mysql_list_dbs($this->conn);
        $i = 0;
        $cnt = mysql_num_rows($rsPtr);
        while ($i < $cnt) {
            $rs[] = mysql_db_name($rsPtr, $i);
            $i++;
        }
        return $rs;
    }

    
    public function show_tables($database_name) {
        $this->query("show tables");
        echo "现有数据库：" . $amount = $this->db_num_rows($rs);
        echo "<br />";
        $i = 1;
        while ($row = $this->fetch_array($rs)) {
            $columnName = "Tables_in_" . $database_name;
            echo "$i $row[$columnName]";
            echo "<br />";
            $i++;
        }
    }

    

    
    public function mysql_result_li() {
        return mysql_result($str);
    }

    
    public function fetch_array() {
        return mysql_fetch_array($this->result);
    }

    //获取关联数组,使用$row['字段名']
    public function fetch_assoc() {
        return mysql_fetch_assoc($this->result);
    }

    //获取数字索引数组,使用$row[0],$row[1],$row[2]
    public function fetch_row() {
        return mysql_fetch_row($this->result);
    }

    //获取对象数组,使用$row->content
    public function fetch_Object() {
        return mysql_fetch_object($this->result);
    }

    //简化查询select
    public function findall($table) {
        $this-&g