The encapsulation and use of PHP database classes

This article introduces the contents of the PHP database class packaging and use, has a certain reference value, now share to everyone, the need for friends can refer to

Encapsulation class

<?php//encapsulates a DB class, which is used to operate the database specifically, and all subsequent operations on the database are implemented by the DB Class object to implement the class db{//attribute private $host;        Private $port;        Private $user;       Private $pass;        Private $dbname;    Private $charset;            Private $prefix;                Table prefix private $link; Connecting the resource (connecting to the database typically returns a resource, so you need to define a link property)//constructor Method (function: To initialize the object's properties), will be automatically called/* * @param1 array $arr, default is empty, inside is          An associative array with 7 elements * Array (' host ' = ' localhost ', ' port ' = ' 3306 ');  */Public Function __construct ($arr = Array ()) {//Initialize $this->host = isset ($arr [' Host ']) ?  $arr [' Host ']: ' localhost ';//First determine if you have your own host, if you have to use your own host, otherwise you will use the default localhost $this->port = isset ($arr [' Port ']) ?             $arr [' Port ']: ' 3306 '; $this->user = isset ($arr [' user '])?            $arr [' User ']: ' Root '; $this->pass = isset ($arr [' Pass '])?             $arr [' Pass ']: ' CZYYZB '; $this->dbname = isset ($arr [' dbname '])?          $arr [' dbname ']: ' mydb ';   $this->charset = isset ($arr [' CharSet '])?             $arr [' CharSet ']: ' UTF8 '; $this->prefix = isset ($arr [' prefix '])?             $arr [' prefix ']: ';             Connect to the database (the class is to manipulate the database, so to connect to the database) $this->connect ();             Sets the character set $this->setcharset ();         Select Database $this->setdbname (); }/* * Connect to Database */Private function connect () {//mysql Extended connection $th Is->link = mysql_connect ($this->host.        ':' .               $this->port, $this->user, $this->pass);                   Judging the result if (! $this->link) {//Result error//violence handling, if true online project (production environment) must be written to log file                   Echo ' Database connection error:<br/> '; Echo ' Error number '. Mysql_errno ().                   ' <br/> '; Echo ' ERROR content '. Mysql_error ().                   ' <br/> ';               Exit }/* * Set Character set */Private function SetCHarset () {//Set $this->db_query ("Set names {$this->charset}"); }/* * Select database */Private Function Setdbname () {$this->db_que            Ry ("Use {$this->dbname}"); }/* Add data * @param1 string $sql, insert statement to execute * @return Boolean, successful return is autogrow ID, Failure returns false */Public function Db_insert ($sql) {//Send data $this                  ->db_query ($sql); Successfully returned the self-increment ID return mysql_affected_rows ()?               MYSQL_INSERT_ID (): FALSE; }/* * Delete data * @param1 string $sql, DELETE statement to execute * @return Boolean, successful                   Returns the number of rows affected, Failure returns false */Public function Db_delete ($sql) {//Send SQL                   $this->db_query ($sql); Judgment result return Mysql_affected_rows () ?               Mysql_affected_rows (): FALSE; }/* * Update data * @param1 string $sql, UPDATE statement to execute * @return Boolean, successfully                   Returns the number of rows affected, Failure returns false */Public function db_update ($sql) {//Send SQL                   $this->db_query ($sql); Judgment result return mysql_affected_rows ()?               Mysql_affected_rows (): FALSE; }/* Query: Query a record * @param1 string $sql, SQL statement to query * @return m                    Ixed, successfully returned an array, failed to return false */Public function Db_getrow ($sql) {//Send SQL                    $res = $this->db_query ($sql); Return mysql_num_rows ($res)?                MYSQL_FETCH_ASSOC ($res): FALSE; }/* Query: Query multiple records * @param1 string $sql, the SQL statement to query * @retu RN mixed, successfully returned a two-dimensional array, failedReturns false */Public function Db_getall ($sql) {//Send SQL                     $res = $this->db_query ($sql); Judgment return if (Mysql_num_rows ($res)) {//Loop traversal $list = Array ()                         ;                         Traverse while ($row = Mysql_fetch_assoc ($res)) {$list [] = $row;                     }//returns return $list;                  }//returns false to false;                   }/* * mysql_query error handling * @param1 string $sql, SQL statement to execute                      * @return mixed, as long as the statement does not go wrong, all return */Private function Db_query ($sql) {                      Send SQL $res = mysql_query ($sql);      Determine the result if (! $res) {                    The result is an error.//Violent handling, if the actual online project (production environment) must be written to the log file echo ' statement errors occurred                          :<br/> '; Echo ' Error number '. Mysql_errno ().                          ' <br/> '; Echo ' ERROR content '. Mysql_error ().                          ' <br/> ';                      Exit                  }//No error return $res;                      }//__sleep method Public function __sleep () {//Returns an array of properties that need to be saved                  Return Array (' Host ', ' Port ', ' user ', ' Pass ', ' dbname ', ' charset ', ' prefix ');                      }//__wakeup method Public function __wakeup () {//Connection resource                      $this->connect ();                      Set character sets and select Database $this->setcharset ();                  $this->setdbname ();             }/* * Get the full table name */     protected function Gettablename () {//Full table name: Prefix + table name return $this->prefix. $                  this->table; }}?>

Use

<? Php

Header ("content-type:text/html; Charset=utf-8 "), Include (" conn.php ");//Instantiate $con = new DB (Array (' dbname ' = ' oilmis_wh ')); $sql =" SELECT * from stock "; $ arr = $con->db_getall ($sql);

? >//this DB class, generally does not write the destructor (does not release the resources)