What is the purpose of using curly braces in PHP variable variables like $this->_session->{$this->_member}?

When using variable variables in PHP, curly braces are used to specify complex variable expressions or nested variables. In the example $this->_session->{$this->_member}, the curly braces are used to access a variable property within an object using another variable. This allows for dynamic variable referencing and helps avoid syntax errors when dealing with complex variable names. 

// Example of using curly braces with variable variables
class Session {
    private $_session = ['user' => 'John'];
    private $_member = 'user';

    public function getSessionMember() {
        return $this->_session->{$this->_member};
    }
}

$session = new Session();
echo $session->getSessionMember(); // Output: John

Keywords

curly braces PHP variable variables object properties dynamic variable names

Related Questions