PHP Object-oriented thinking design MySQL database operation class

 Host=!empty ($config [' Host '])?      $config [' Host ']: "localhost"; $this->port=!empty ($config [' Port ']?      $config [' Port ']: "3306"; $this->user=!empty ($config [' user '])?      $config [' User ']: "root"; $this->password=!empty ($config [' Password '])?      $config [' Password ']: ""; $this->charset=!empty ($config [' CharSet '])?      $config [' CharSet ']: "UTF8"; $this->dbname=!empty ($config [' dbname '])?      $config [' dbname ']: ""; $this->link= mysql_connect ("{$this->host}:{$this->port}", "{$this->user}", "{$this->password}") O      R die (' execution failed ');      $this->setcharset ($this->charset);   $this->usedbname ($this->dbname);   }//single case design mode static $temp =null;      static function GetClass () {if (!isset (self:: $temp)) {$class-=new self ();      }else{return self:: $temp;   }}//You can set the encoding function Setcharset ($charset) {mysql_query ("Set names $charset");   }//You can set the database function Usedbname ($dbname) {mysql_query ("use $dbname") to be connected; }   You can turn off database function Closedb () {mysql_close ($this->link);   echo "closed successfully!";}         Execute a Delete and modify statement, return the true and false result function exec ($sql) {$result = $this->query ($sql);      return true;         }//Returns a row of query data function Gerrow ($sql) {$result = $this->query ($sql);      $array =mysql_fetch_array ($result);      Mysql_free_result ($result);//release resources return $array;         }//returns multiple rows of query data function getRows ($sql) {$result = $this->query ($sql);         $arr =array ();         while ($array =mysql_fetch_array ($result)) {$arr []= $array;      } mysql_free_result ($result);//Release the resource return $arr;      }//Returns a statement of the data that can return a direct value function Getonedata ($sql) {$result = $this->query ($sql);      $array =mysql_fetch_array ($result);      $data = $array [0];   Mysql_free_result ($result);//release resources return $data;      }//can execute any SQL statement and error handling, or return execution result function query ($sql) {$result =mysql_query ($sql, $this->link); if ($result ===false) {echo]
Execution failure, see the following information: "; Echo
Error code: ". Mysql_errno (); Echo
Error message: ". Mysql_error (); Echo
Error statement: ". $sql;      Die ();      }else{return $result; }   }}

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