php - using $this when not in object's context error -

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• php fatal error: using $this when not in object context 9 answers

here have class called db used prepare pdo statement , perform select, insert etc on pdo object.here trying insert data collected html form.but when execute code gives me error mentioned in question. both getinstance() , insert() public static function.can me solve problem?

class db{         private static $_instance=null;         private $pdo,                 $query,                 $error=false,                 $results,                 $count=0;         private function __construct(){                 try{                      $this->pdo=new pdo('mysql:host='.config::get('mysql/host').';dbname='.config::get('mysql/db'),config::get('mysql/user'),config::get('mysql/password'));                   }catch(pdoexception  $e){                     echo $e->getmessage();                 }         }         public static function getinstance(){             if(!isset(self::$_instance)){                   self::$_instance=new db();             }             return self::$_instance;         }          private function bind($val){                $i=1;                foreach($val $data){                     $this->query->bindvalue($i,$data);                 }                $i++;          }         public static function insert(){             $stmt='insert users (username,password,name) values (?,?,?)';             if($this->query=$this->pdo->prepare($stmt)){                 $val=validate::send();                 $this->bind($val);                 if($this->query->execute()){                     return 'successfull';                 }             }         }     }  

and invoked them like:

if(isset($_post['submit'])){         $insert=db::getinstance();         $insert::insert();     }    

you're using $this in static function. why got error.

remove "static" in front of "insert()" , call $insert->insert();