一个通用的PHP连接MYSQL数据库类

一个普遍通用的PHP连接MYSQL数据库类

<?php

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

         /*构造函数*/

         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();

         }

         /*数据库连接*/

         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");

         }

    

         /*数据库执行语句,可执行查询添加修改删除等任何sql语句*/

         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;

         }

         /*创建添加新的数据库*/

         public function create_database($database_name) {

                   $database = $database_name;

                   $sqlDatabase = 'create database ' . $database;

                   $this->query($sqlDatabase);

         }

         /*查询服务器所有数据库*/

         //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;

         }

         /*查询数据库下所有的表*/

         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++;

                   }

         }

         /*

         mysql_fetch_row()    array  $row[0],$row[1],$row[2]

         mysql_fetch_array()  array  $row[0] 或 $row[id]

         mysql_fetch_assoc()  array  用$row->content 字段大小写敏感

         mysql_fetch_object() object 用$row[id],$row[content] 字段大小写敏感

         */

         /*取得结果数据*/

         public function mysql_result_li() {

                   return mysql_result($str);

         }

         /*取得记录集,获取数组-索引和关联,使用$row['content'] */

         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->query("SELECT * FROM $table");

         }

         //简化查询select

         public function select($table, $columnName = "*", $condition = '', $debug = '') {

                   $condition = $condition ? ' Where ' . $condition : NULL;

                   if ($debug) {

                            echo "SELECT $columnName FROM $table $condition";

                   } else {

                            $this->query("SELECT $columnName FROM $table $condition");

                   }

         }

         //简化删除del

         public function delete($table, $condition, $url = '') {

                   if ($this->query("DELETE FROM $table WHERE $condition")) {

                            if (!empty ($url))

                                     $this->Get_admin_msg($url, '删除成功!');

                   }

         }

         //简化插入insert

         public function insert($table, $columnName, $value, $url = '') {

                   if ($this->query("INSERT INTO $table ($columnName) VALUES ($value)")) {

                            if (!empty ($url))

                                     show_msg($url, '添加成功!');

                   }

         }

         //简化修改update

         public function update($table, $mod_content, $condition, $url = '') {

                  

                   if ($this->query("UPDATE $table SET $mod_content WHERE $condition")) {

                            if (!empty ($url))

                                     show_msg($url);

                   }

         }

         /*取得上一步 INSERT 操作产生的 ID*/

         public function insert_id() {

                   return mysql_insert_id();

         }

         //指向确定的一条数据记录

         public function db_data_seek($id) {

                   if ($id > 0) {

                            $id = $id -1;

                   }

                   if (!@ mysql_data_seek($this->result, $id)) {

                            $this->show_error("SQL语句有误:", "指定的数据为空");

                   }

                   return $this->result;

         }

         // 根据select查询结果计算结果集条数

         public function db_num_rows() {

                   if ($this->result == null) {

                            if ($this->show_error) {

                                     $this->show_error("SQL语句错误", "暂时为空,没有任何内容!");

                            }

                   } else {

                            return mysql_num_rows($this->result);

                   }

         }

         // 根据insert,update,delete执行结果取得影响行数

         public function db_affected_rows() {

                   return mysql_affected_rows();

         }

         //输出显示sql语句

         public function show_error($message = "", $sql = "") {

                   if (!$sql) {

                            echo "<font color='red'>" . $message . "</font>";

                            echo "<br />";

                   } else {

                            echo "<fieldset>";

                            echo "<legend>错误信息提示:</legend><br />";

                            echo "<div style='font-size:14px; clear:both; font-family:Verdana, Arial, Helvetica, sans-serif;'>";

                            echo "<div style='height:20px; background:#000000; border:1px #000000 solid'>";

                            echo "<font color='white'>错误号:12142</font>";

                            echo "</div><br />";

                            echo "错误原因:" . mysql_error() . "<br /><br />";

                            echo "<div style='height:20px; background:#FF0000; border:1px #FF0000 solid'>";

                            echo "<font color='white'>" . $message . "</font>";

                            echo "</div>";

                            echo "<font color='red'><pre>" . $sql . "</pre></font>";

                            //$ip = $this->getip();

                            if ($this->bulletin) {

                                     $time = date("Y-m-d H:i:s");

                                     $message = $message . " $this->sql" . " 客户IP:$ip" . " 时间 :$time" . " ";

                                     $server_date = date("Y-m-d");

                                     $filename = $server_date . ".txt";

                                     $file_path = "error/" . $filename;

                                     $error_content = $message;

                                     //$error_content="错误的数据库,不可以链接";

                                     $file = "error"; //设置文件保存目录

                                     //建立文件夹

                                     if (!file_exists($file)) {

                                               if (!mkdir($file, 0777)) {

                                                        //默认的 mode 是 0777,意味着最大可能的访问权

                                                        die("upload files directory does not exist and creation failed");

                                               }

                                     }

                                     //建立txt日期文件

                                     if (!file_exists($file_path)) {

                                               //echo "建立日期文件";

                                               fopen($file_path, "w+");

                                               //首先要确定文件存在并且可写

                                               if (is_writable($file_path)) {

                                                        //使用添加模式打开$filename,文件指针将会在文件的开头

                                                        if (!$handle = fopen($file_path, 'a')) {

                                                                 echo "不能打开文件 $filename";

                                                                 exit;

                                                        }

                                                        //将$somecontent写入到我们打开的文件中。

                                                        if (!fwrite($handle, $error_content)) {

                                                                 echo "不能写入到文件 $filename";

                                                                 exit;

                                                        }

                                                        //echo "文件 $filename 写入成功";

                                                        echo "——错误记录被保存!";

                                                        //关闭文件

                                                        fclose($handle);

                                               } else {

                                                        echo "文件 $filename 不可写";

                                               }

                                     } else {

                                               //首先要确定文件存在并且可写

                                               if (is_writable($file_path)) {

                                                        //使用添加模式打开$filename,文件指针将会在文件的开头

                                                        if (!$handle = fopen($file_path, 'a')) {

                                                                 echo "不能打开文件 $filename";

                                                                 exit;

                                                        }

                                                        //将$somecontent写入到我们打开的文件中。

                                                        if (!fwrite($handle, $error_content)) {

                                                                 echo "不能写入到文件 $filename";

                                                                 exit;

                                                        }

                                                        //echo "文件 $filename 写入成功";

                                                        echo "——错误记录被保存!";

                                                        //关闭文件

                                                        fclose($handle);

                                               } else {

                                                        echo "文件 $filename 不可写";

                                               }

                                     }

                            }

                            echo "<br />";

                            if ($this->is_error) {

                                     exit;

                            }

                   }

                   echo "</div>";

                   echo "</fieldset>";

                   echo "<br />";

         }

         //释放结果集

         public function free() {

                   @ mysql_free_result($this->result);

         }

         //数据库选择

         public function select_db($db_database) {

                   return mysql_select_db($db_database);

         }

         //查询字段数量

         public function num_fields($table_name) {

                   //return mysql_num_fields($this->result);

                   $this->query("select * from $table_name");

                   echo "<br />";

                   echo "字段数:" . $total = mysql_num_fields($this->result);

                   echo "<pre>";

                   for ($i = 0; $i < $total; $i++) {

                            print_r(mysql_fetch_field($this->result, $i));

                   }

                   echo "</pre>";

                   echo "<br />";

         }

         //取得 MySQL 服务器信息

         public function mysql_server($num = '') {

                   switch ($num) {

                            case 1 :

                                     return mysql_get_server_info(); //MySQL 服务器信息

                                     break;

                            case 2 :

                                     return mysql_get_host_info(); //取得 MySQL 主机信息

                                     break;

                            case 3 :

                                     return mysql_get_client_info(); //取得 MySQL 客户端信息

                                     break;

                            case 4 :

                                     return mysql_get_proto_info(); //取得 MySQL 协议信息

                                     break;

                            default :

                                     return mysql_get_client_info(); //默认取得mysql版本信息

                   }

         }

         //析构函数,自动关闭数据库,垃圾回收机制

         public function __destruct() {

                   if (!empty ($this->result)) {

                            $this->free();

                   }

                   mysql_close($this->conn);

         } //function __destruct();

}?>

原文地址:https://www.cnblogs.com/yuanscn/p/10931846.html