PHP的数据库操作类
2014-09-05来源:易贤网
,p>$db = new mysql($db_host,$db_user,$db_password,$db_table,$db_conn,$pre,$coding);

class mysql{

private $db_host;

private $db_user;

private $db_password;

private $db_table;

private $db_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 $pre; //数据库表前缀

private $coding; //数据库编码,GBK,UTF8,gb2312

function __construct($db_host,$db_user,$db_password,$db_table,$db_conn,$pre,$coding){

$this->db_host = $db_host;

$this->db_user = $db_user;

$this->db_password = $db_password;

$this->db_table = $db_table;

$this->db_conn = $db_conn;

$this->pre = $pre;

$this->coding = $coding;

$this->connect();

}

function connect(){

$this->db_conn = @mysql_connect($this->db_host,$this->db_user,$this->db_password) or die($this->show_error("数据库链接错误,请检查数据库链接配置!"));

if(!mysql_select_db($this->db_table,$this->db_conn)){

echo "没有找到数据表:".$this->db_table;

}

mysql_select_db($this->db_table,$this->db_conn);

$this->query("SET NAMES $this->coding");

}

/*执行SQL语句的函数*/

function query($sql){

if(emptyempty($sql)){

$this->show_error("你的sql语句不能为空!");

}else{

$this->sql = $sql;

}

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

return $this->result = $result;

}

/*创建添加新的数据库*/

public function create_database($database_name){

$database=$database_name;

$sqlDatabase = 'create database '.$database;

return $this->query($sqlDatabase);

}

// 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!");

}

}else{

return mysql_num_rows($this->result);

}

}

/*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 "";

$i=1;

while($row = $this->fetch_array($rs)){

echo "$i $row[Database]";

echo "";

$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->db_conn);

$i=0;

$cnt=mysql_num_rows($rsPtr);

while($i<$cnt)

{

$rs[]=mysql_db_name($rsPtr,$i);

$i++;

}

return print_r($rs);

}

/*查询数据库下所有的表*/

function show_tables($database_name){

$this->query("show tables");

echo "现有数据库:".$amount = $this->db_num_rows($rs);

echo "";

$i=1;

while($row = $this->fetch_array($rs)){

$columnName="Tables_in_".$database_name;

echo "$i $row[$columnName]";

echo "";

$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_ass()

{

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){

$table = $this->fulltablename($table);

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

}

public function select($table,$columnName,$condition){

$table = $this->fulltablename($table);

if(emptyempty($columnName)){

$columnName = "*";

}

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

}

//简化的insert

function insert($table,$arr){

$table = $this->fulltablename($table);

$sql = "INSERT INTO $table ";

if(!is_array($arr)){

$this->show_error("请输入参数数组!");

}else{

$k = "";

$v = "";

foreach($arr as $key => $value){

$k .= "`$key`,";

$v .= "'".$value."',";

}

}

$sql = $sql." (".substr($k,0,-1).") VALUES (".substr($v,0,-1).")";

$this->query($sql);

}

//简化的update

function update($table,$arr,$where){

$table = $this->fulltablename($table);

$sql = "UPDATE $table SET ";

if(!is_array($arr)){

$this->show_error("请输入参数数组!");

}else{

foreach($arr as $key => $value){

$sql .= " `".$key."` = '".$value."' ,";

}

}

$sql = substr($sql,0,-1)." where ".$where;

return $this->query($sql);

}

//简化的delete

function delete($table,$where = ""){

$table = $this->fulltablename($table);

if(emptyempty($where)){

$this->show_error("条件不能为空!");

}else{

$where = " where ".$where;

}

$sql = "DELETE FROM $table ".$where;

//echo $sql;

return $this->query($sql);

}

//取得上一步 INSERT 操作产生的 ID

public function insert_id(){

return mysql_insert_id();

}

//加上前缀的数据表

public function fulltablename($table){

return $table = $this->pre.$table;

}

//查询字段数量

public function num_fields($table){

$table = $this->fulltablename($table);

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

echo "";

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

echo "

";

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

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

}

echo "";

echo "";

}

//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($this->$db_conn);

}*/

/*获得客户端真实的IP地址*/

function getip(){

if(getenv("HTTP_CLIENT_IP") && strcasecmp(getenv("HTTP_CLIENT_IP"), "unknown"))

{

$ip = getenv("HTTP_CLIENT_IP");

}

else if (getenv("HTTP_X_FORWARDED_FOR") && strcasecmp(getenv("HTTP_X_FORWARDED_FOR"), "unknown")){

$ip = getenv("HTTP_X_FORWARDED_FOR");

}

else if (getenv("REMOTE_ADDR") && strcasecmp(getenv("REMOTE_ADDR"), "unknown"))

{

$ip = getenv("REMOTE_ADDR");

}

else if (isset($_SERVER['REMOTE_ADDR']) && $_SERVER['REMOTE_ADDR'] && strcasecmp($_SERVER['REMOTE_ADDR'], "unknown")){

$ip = $_SERVER['REMOTE_ADDR'];

}

else{

$ip = "unknown";

}

return($ip);

}

function show_error($str){

echo "Javascript'> alert('".$str."');history.back(-1);";

}

}

?>

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