Question

I read about this Article
I wondering about this part:

try {
    //First try getting our user numero uno
    $user = new User(1);

    //Then, let's try to get the exception
    $user2 = new User('not numeric');
} catch( Exception $e ) {
    echo "Donkey Kong has caught an exception: {$e->getMessage()}";
}

why {$e->getMessage()} must be covered in bracket?
Is there any link explanation on php manual about this?

i know if we don’t put bracket it will show error, but want i want is to get the explanation why bracket is needed.

Notice: Undefined property: Exception::$getMessage

Answer 1

It has to do with the fact that this is a complex expression. If you don’t include the bracket, i.e.:

echo "Donkey Kong has caught an exception: $e->getMessage()";

…then how does PHP know what variable you’re trying to output? You could be trying to do any of the following:

• output the value of $e, followed by the string “->getMessage()”
• output the value of $e->getMessage, followed by the string “()”
• output the value of $e->getMessage()

Placing the brackets around the full expression tells PHP the full expression that needs to be evaluated and included in the string.