php - password_hash giving error: Strict standards: Only variables should be passed by reference -

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• what difference between bindparam , bindvalue? 7 answers

edit: issue has been resolved. did not know or think of bindvalue(), why not think duplicate question. help!

i learning how register users php , seems password_hash giving me "only variables should passed reference" error message. i've seen many people same error, not seem apply case (in opinion).

connecting database

$server = 'localhost'; $username ='root'; $password ='root'; $database = 'register_test';  try{     $conn = new pdo("mysql:host=$server;dbname=$database;" , $username, $password); } catch(pdoexception $e){     die ("connection failed" . $e->getmessage()); } 

registering user

require 'database.php'; if(!empty($_post['email']) && !empty($_post['password'])):  $pass = $_post['password']; $email = $_post['email'];  $sql = "insert user (email, password) values (:email, :password)"; $stmt = $conn->prepare($sql);  $stmt ->bindparam(':email', $email); $stmt ->bindparam(':password', password_hash($pass, password_bcrypt)); //error showns here  if($stmt -> execute() ):   die('success'); else:   die('fail'); endif; endif; 

if guys need more information please let me know.

use pdostatement::bindvalue() instead of pdostatement::bindparam().

from docs:

unlike pdostatement::bindvalue(), variable bound reference , evaluated @ time pdostatement::execute() called.

so, code becomes:

$stmt->bindvalue(':email', $email); $stmt->bindvalue(':password', password_hash($pass, password_bcrypt));  

the result of function cannot passed reference when e_strict mode enabled, without triggering warning. using bindvalue() instead, pass return value of function copy, basically.