数据库操作类

php代码    

<?php
/*
 * 数据库操作类
 *
 */


class Mysql {
    private $server = "";
    private $user = "";
    private $password = "";
    private $database = "";
    private $linkMode = 1;
    private $link_id = 0;
    private $query_id = 0;
    private $query_times = 0;
    private $result = array ();
    private $fetchMode = MYSQL_ASSOC;
    private $err_no = 0;
    private $err_msg;
    private $character;
    //======================================
    // 函数: mysql()
    // 功能: 构造函数
    // 参数: 参数类的变量定义
    // 说明: 构造函数将自动连接数据库
    // 如果想手动连接去掉自动连接函数
    //======================================
    public function __construct($server, $user, $password, $database, $character = "UTF8", $linkMode = 0) {
        if (empty ( $server ) || empty ( $user ) || empty ( $database ))
            $this->halt ( "提交的数据库信息不完整！请检查服务器地址，用户和数据库是否正确有效" );

        $this->server = $server;
        $this->user = $user;
        $this->password = $password;
        $this->database = $database;
        $this->linkMode = $linkMode;
        $this->character = $character;
        $this->connect ();
    }
    //======================================
    // 函数: connect($server,$user,$password,$database)
    // 功能: 连接数据库
    // 参数: $server 主机名, $user 用户名
    // 参数: $password 密码, $database 数据库名称
    // 返回: 0:失败
    // 说明: 默认使用类中变量的初始值
    //======================================
    public function connect($server = "", $user = "", $password = "", $database = "") {
        $server = $server ? $server : $this->server;
        $user = $user ? $user : $this->user;
        $password = $password ? $password : $this->password;
        $database = $database ? $database : $this->database;

        $this->link_id = $this->linkMode ? mysql_pconnect ( $server, $user, $password, $database ) : mysql_connect ( $server, $user, $password, $database );

        if (! $this->link_id) {
            $this->halt ( "数据库连接失败！请检查各项参数！" );
            return 0;
        }

        if (! mysql_select_db ( $database, $this->link_id )) {
            $this->halt ( "无法选择数据库" );
            return 0;
        }

        if ($this->character != "GBK" && $this->character != "UTF8") {
            $this->halt ( "输入的编码模式不正确！" );
            return 0;
        }

        $this->query ( &#39;SET NAMES &#39; . $this->character );
        return $this->link_id;
    }
    //======================================
    // 函数: query($sql)
    // 功能: 数据查询
    // 参数: $sql 要查询的SQL语句
    // 返回: 0:失败
    //======================================
    public function query($sql) {
        $this->query_times ++;
        $this->query_id = mysql_query ( $sql, $this->link_id );
        if (! $this->query_id) {
            $this->halt ( "<font color=red>" . $sql . "</font> 语句执行不成功！" );
            return 0;
        }

        return $this->query_id;
    }
    //======================================
    // 函数: setFetchMode($mode)
    // 功能: 设置取得记录的模式
    // 参数: $mode 模式 MYSQL_ASSOC, MYSQL_NUM, MYSQL_BOTH
    // 返回: 0:失败
    //======================================
    public function setFetchMode($mode) {
        if ($mode == MYSQL_ASSOC || $mode == MYSQL_NUM || $mode == MYSQL_BOTH) {
            $this->fetchMode = $mode;
            return 1;
        } else {
            $this->halt ( "错误的模式." );
            return 0;
        }
    }
    //======================================
    // 函数: fetchRow()
    // 功能: 从记录集中取出一条记录
    // 返回: 0: 出错 record: 一条记录
    //======================================
    public function fetchRow() {
        $this->record = mysql_fetch_array ( $this->query_id, $this->fetchMode );

        return $this->record;
    }
    //======================================
    // 函数: fetchAll()
    // 功能: 从记录集中取出所有记录
    // 返回: 记录集数组
    //======================================
    public function fetchAll() {
        $arr [] = array ();

        while ( $this->record = mysql_fetch_array ( $this->query_id, $this->fetchMode ) )
            $arr [] = $this->record;

        mysql_free_result ( $this->query_id );
        return $arr;
    }
    //======================================
    // 函数: getValue()
    // 功能: 返回记录中指定字段的数据
    // 参数: $field 字段名或字段索引
    // 返回: 指定字段的值
    //======================================
    public function getValue($filed) {
        return $this->record [$filed];
    }
    //======================================
    // 函数: getquery_id()
    // 功能: 返回查询号
    //======================================
    public function getquery_id() {
        return $this->query_id;
    }
    //======================================
    // 函数: affectedRows()
    // 功能: 返回影响的记录数
    //======================================
    public function affectedRows() {
        return mysql_affected_rows ( $this->link_id );
    }
    //======================================
    // 函数: recordCount()
    // 功能: 返回查询记录的总数
    // 参数: 无
    // 返回: 记录总数
    //======================================
    public function recordCount() {
        return mysql_num_rows ( $this->query_id );
    }
    //======================================
    // 函数: getquery_times()
    // 功能: 返回查询的次数
    // 参数: 无
    // 返回: 查询的次数
    //======================================
    public function getquery_times() {
        return $this->query_times;
    }
    //======================================
    // 函数: getVersion()
    // 功能: 返回mysql的版本
    // 参数: 无
    //======================================
    public function getVersion() {
        $this->query ( "select version() as ver" );
        $this->fetchRow ();
        return $this->getValue ( "ver" );
    }
    //======================================
    // 函数: getDBSize($database, $tblPrefix=null)
    // 功能: 返回数据库占用空间大小
    // 参数: $database 数据库名
    // 参数: $tblPrefix 表的前缀,可选
    //======================================
    public function getDBSize($database, $tblPrefix = null) {
        $sql = "SHOW TABLE STATUS FROM " . $database;
        if ($tblPrefix != null) {
            $sql .= " LIKE &#39;$tblPrefix%&#39;";
        }
        $this->query ( $sql );
        $size = 0;
        while ( $this->fetchRow () )
            $size += $this->getValue ( "Data_length" ) + $this->getValue ( "Index_length" );
        return $size;
    }
    //======================================
    // 函数: halt($err_msg)
    // 功能: 处理所有出错信息
    // 参数: $err_msg 自定义的出错信息
    //=====================================
    public function halt($err_msg = "") {
        if ($err_msg == "") {
            $this->errno = mysql_errno ();
            $this->error = mysql_error ();
            echo "<b>mysql error:<b><br>";
            echo $this->errno . ":" . $this->error . "<br>";
            exit ();
        } else {
            echo "<b>mysql error:<b><br>";
            echo $err_msg . "<br>";
            exit ();
        }
    }
    //======================================
    // 函数: insertID()
    // 功能: 返回最后一次插入的自增ID
    // 参数: 无
    //======================================
    public function insertID() {
        return mysql_insert_id ();
    }
    //======================================
    //函数：close()
    //功能：关闭非永久的数据库连接
    //参数：无
    //======================================
    public function close() {
        $link_id = $link_id ? $link_id : $this->link_id;
        mysql_close ( $link_id );
    }
    //======================================
    // 函数: sqlSelect()
    // 功能: 返回组合的select查询值
    // 参数: $tbname 查询的表名
    // 参数: $where 条件
    // 参数: $fields 字段值
    // 参数: $orderby 按某字段排序
    // 参数: $sort 正序ASC,倒序DESC,$orderby 不为空是有效
    // 参数: $limit 取得记录的条数,0,8
    // 返回: 查询语句
    //======================================
    function sqlSelect($tbname, $where = "", $limit = 0, $fields = "*", $orderby = "", $sort = "DESC") {
        $sql = "SELECT " . $fields . " FROM " . $tbname . ($where ? " WHERE " . $where : "") . ($orderby ? " ORDER BY " . $orderby . " " . $sort : "") . ($limit ? " limit " . $limit : "");
        return $sql;
    }
    //======================================
    // 函数: sqlInsert()
    // 功能: Insert插入数据函数
    // 参数: $taname 要插入数据的表名
    // 参数: $row 要插入的内容 (数组)
    // 返回: 记录总数
    // 返回: 插入语句
    //======================================
    function sqlInsert($tbname, $row) {
        foreach ( $row as $key => $value ) {
            $sqlfield .= $key . ",";
            $sqlvalue .= "&#39;" . $value . "&#39;,";
        }
        return "INSERT INTO " . $tbname . "(" . substr ( $sqlfield, 0, - 1 ) . ") VALUES (" . substr ( $sqlvalue, 0, - 1 ) . ")";
    }
    //======================================
    // 函数: sqlUpdate()
    // 功能: Update更新数据的函数
    // 参数: $taname 要插入数据的表名
    // 参数: $row 要插入的内容 (数组)
    // 参数: $where 要插入的内容 的条件
    // 返回: Update语句
    //======================================
    function sqlUpdate($tbname, $row, $where) {
        foreach ( $row as $key => $value ) {
            $sqlud .= $key . "= &#39;" . $value . "&#39;,";
        }
        return "UPDATE " . $tbname . " SET " . substr ( $sqlud, 0, - 1 ) . " WHERE " . $where;
    }
    //======================================
    // 函数: sqlDelete()
    // 功能: 删除指定条件的行
    // 参数: $taname 要插入数据的表名
    // 参数: $where 要插入的内容 的条件
    // 返回: DELETE语句
    //======================================
    function sqlDelete($tbname, $where) {
        if (! $where) {
            $this->halt ( "删除函数没有指定条件！" );
            return 0;
        }
        return "DELETE FROM " . $tbname . " WHERE " . $where;
    }

    //======================================
    //函数：checkSql SQL语句的过滤
    //功能：过滤一些特殊语法
    //参数：$db_string 查询的SQL语句
    //参数：$querytype 查询的类型
    //======================================
    function checkSql($db_string, $querytype = &#39;select&#39;) {
        $clean = &#39;&#39;;
        $old_pos = 0;
        $pos = - 1;

        //如果是普通查询语句，直接过滤一些特殊语法
        if ($querytype == &#39;select&#39;) {
            $notallow1 = "[^0-9a-z@\._-]{1,}(union|sleep|benchmark|load_file|outfile)[^0-9a-z@\.-]{1,}";

            //$notallow2 = "--|/\*";
            if (eregi ( $notallow1, $db_string )) {
                exit ( "<font size=&#39;5&#39; color=&#39;red&#39;>Safe Alert: Request Error step 1 !</font>" );
            }
        }

        //完整的SQL检查
        while ( true ) {
            $pos = strpos ( $db_string, &#39;\&#39;&#39;, $pos + 1 );
            if ($pos === false) {
                break;
            }
            $clean .= substr ( $db_string, $old_pos, $pos - $old_pos );
            while ( true ) {
                $pos1 = strpos ( $db_string, &#39;\&#39;&#39;, $pos + 1 );
                $pos2 = strpos ( $db_string, &#39;\\&#39;, $pos + 1 );
                if ($pos1 === false) {
                    break;
                } elseif ($pos2 == false || $pos2 > $pos1) {
                    $pos = $pos1;
                    break;
                }
                $pos = $pos2 + 1;
            }
            $clean .= &#39;$s$&#39;;
            $old_pos = $pos + 1;
        }
        $clean .= substr ( $db_string, $old_pos );
        $clean = trim ( strtolower ( preg_replace ( array (&#39;~\s+~s&#39; ), array (&#39; &#39; ), $clean ) ) );

        //老版本的Mysql并不支持union，常用的程序里也不使用union，但是一些黑客使用它，所以检查它
        if (strpos ( $clean, &#39;union&#39; ) !== false && preg_match ( &#39;~(^|[^a-z])union($|[^[a-z])~s&#39;, $clean ) != 0) {
            $fail = true;
        }

        //发布版本的程序可能比较少包括--,#这样的注释，但是黑客经常使用它们
        elseif (strpos ( $clean, &#39;/*&#39; ) > 2 || strpos ( $clean, &#39;--&#39; ) !== false || strpos ( $clean, &#39;#&#39; ) !== false) {
            $fail = true;
        }

        //这些函数不会被使用，但是黑客会用它来操作文件，down掉数据库
        elseif (strpos ( $clean, &#39;sleep&#39; ) !== false && preg_match ( &#39;~(^|[^a-z])sleep($|[^[a-z])~s&#39;, $clean ) != 0) {
            $fail = true;
        } elseif (strpos ( $clean, &#39;benchmark&#39; ) !== false && preg_match ( &#39;~(^|[^a-z])benchmark($|[^[a-z])~s&#39;, $clean ) != 0) {
            $fail = true;
        } elseif (strpos ( $clean, &#39;load_file&#39; ) !== false && preg_match ( &#39;~(^|[^a-z])load_file($|[^[a-z])~s&#39;, $clean ) != 0) {
            $fail = true;
        } elseif (strpos ( $clean, &#39;into outfile&#39; ) !== false && preg_match ( &#39;~(^|[^a-z])into\s+outfile($|[^[a-z])~s&#39;, $clean ) != 0) {
            $fail = true;
        }

        //老版本的MYSQL不支持子查询，我们的程序里可能也用得少，但是黑客可以使用它来查询数据库敏感信息
        elseif (preg_match ( &#39;~\([^)]*?select~s&#39;, $clean ) != 0) {
            $fail = true;
        }
        if (! empty ( $fail )) {
            exit ( "<font size=&#39;5&#39; color=&#39;red&#39;>Safe Alert: Request Error step 2!</font>" );
        } else {
            return $db_string;
        }
    }
    //======================================
    //函数：析构函数
    //功能：释放类，关闭非永久的数据库连接
    //参数：无
    //======================================
    public function __destruct() {
        $this->close ();
    }
}
?>