Php – When to use ErrorException vs Exception

PHP

PHP 5.1 has introduced ErrorException. The constructor of the two functions differs

public __construct ([ string $message = "" [, int $code = 0 [, Exception $previous = NULL ]]] )
public __construct ([ string $message = "" [, int $code = 0 [, int $severity = 1 [, string $filename = __FILE__ [, int $lineno = __LINE__ [, Exception $previous = NULL ]]]]]] )

Is there a difference when to use either?

I suspect that the above use case is incorrect:

<?php
class Data {
    public function save () {
        try {
            // do something
        } catch (\PDOException $e) {
            if ($e->getCode() == '23000') {
                throw new Data_Exception('Foo Bar', $e);
            }

            throw $e
        }
    }
}

class Data_Exception extends ErrorException /* This should not be using ErrorException */ {}

It isn't documented well, but it appears that ErrorException is designed to be used explicitly from the custom error handler as in the original example, http://php.net/manual/en/class.errorexception.php.

function exception_error_handler($errno, $errstr, $errfile, $errline ) {
    throw new ErrorException($errstr, $errno, 0, $errfile, $errline);
}
set_error_handler("exception_error_handler");

Best Answer

ErrorException is mostly used to convert php error (raised by error_reporting) to Exception.

You should avoid using directly Exception which is too wide. Subclass it with specific Exception or use predefined SPL Exception

To follow your edit : Yes extends Exception rather than ErrorException.

Related Solutions

Php – How to use PHP to get the current year

You can use either date or strftime. In this case I'd say it doesn't matter as a year is a year, no matter what (unless there's a locale that formats the year differently?)

For example:

<?php echo date("Y"); ?>

On a side note, when formatting dates in PHP it matters when you want to format your date in a different locale than your default. If so, you have to use setlocale and strftime. According to the php manual on date:

To format dates in other languages, you should use the setlocale() and strftime() functions instead of date().

From this point of view, I think it would be best to use strftime as much as possible, if you even have a remote possibility of having to localize your application. If that's not an issue, pick the one you like best.

Php – When should I use ‘self’ over ‘$this’

Short Answer

Use $this to refer to the current object. Use self to refer to the current class. In other words, use $this->member for non-static members, use self::$member for static members.

Full Answer

Here is an example of correct usage of $this and self for non-static and static member variables:

<?php
class X {
    private $non_static_member = 1;
    private static $static_member = 2;

    function __construct() {
        echo $this->non_static_member . ' '
           . self::$static_member;
    }
}

new X();
?>

Here is an example of incorrect usage of $this and self for non-static and static member variables:

<?php
class X {
    private $non_static_member = 1;
    private static $static_member = 2;

    function __construct() {
        echo self::$non_static_member . ' '
           . $this->static_member;
    }
}

new X();
?>

Here is an example of polymorphism with $this for member functions:

<?php
class X {
    function foo() {
        echo 'X::foo()';
    }

    function bar() {
        $this->foo();
    }
}

class Y extends X {
    function foo() {
        echo 'Y::foo()';
    }
}

$x = new Y();
$x->bar();
?>

Here is an example of suppressing polymorphic behaviour by using self for member functions:

<?php
class X {
    function foo() {
        echo 'X::foo()';
    }

    function bar() {
        self::foo();
    }
}

class Y extends X {
    function foo() {
        echo 'Y::foo()';
    }
}

$x = new Y();
$x->bar();
?>

The idea is that $this->foo() calls the foo() member function of whatever is the exact type of the current object. If the object is of type X, it thus calls X::foo(). If the object is of type Y, it calls Y::foo(). But with self::foo(), X::foo() is always called.

From http://www.phpbuilder.com/board/showthread.php?t=10354489:

By http://board.phpbuilder.com/member.php?145249-laserlight