php准备语句绑定一个会话[重复]

Question

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• Reference: What is variable scope, which variables are accessible from where and what are “undefined variable” errors? 3 answers

How can I set a SESSION and bind it in a prepared statement, so I can get a result from mysqli where email is equal to my SESSION['email']?

I have this code that I can't get to work, so it only gets the result with my session email:

public static function getById($email) {

// Initialize session array
$email = $_SESSION['email'];

// Build database query
$sql = "select * from users where email = ?";

// Open database connection
$database = new Database();

// Get instance of statement
$statement = $database->stmt_init();

// Prepare query
if ($statement->prepare($sql)) {

// Bind parameters
$statement->bind_param('s', $email);

// Execute statement
$statement->execute();

// Bind variable to prepared statement
$statement->bind_result($id, $first_name, $last_name, $username, $email,     $created, $active);

// Populate bind variables
$statement->fetch();

// Close statement
$statement->close();
}

// Close database connection
$database->close();

// Build new object
$object = new self;
$object->id = $id;
$object->first_name = $first_name;
$object->last_name = $last_name;
$object->username = $username;
$object->email = $email;
$object->created = $created;
$object->active = $active;
return $object;
}

</div>

Answer 1

$variable = "I am a variable";

function getVariable() {
    echo $variable;
}

Q) Why would the above script error? A) Scopes...

the $_SESSION['email'] cannot be accessed inside your method, you'll need to either global or define it or pass it in as an parameter.

function getById($email)
{
    echo $email;
}

session_start();
getById($_SESSION['email']);