Passing a boolean through PHP GET

Pretty simple question here, not sure the answer though. Can I pass a boolean variable through get? For example:

http://example.com/foo.php?myVar=true

then I have

$hopefullyBool = $_GET['myVar'];

Is $hopefullyBool a boolean or a string? My hypothesis is that it's a string but can someone let me know? Thanks

Answer

All GET parameters will be strings in PHP. Use filter_var and FILTER_VALIDATE_BOOLEAN:

Returns TRUE for "1", "true", "on" and "yes". Returns FALSE otherwise.

If FILTER_NULL_ON_FAILURE is set, FALSE is returned only for "0", "false", "off", "no", and "", and NULL is returned for all non-boolean values.

$hopefullyBool = filter_var($_GET['myVar'], FILTER_VALIDATE_BOOLEAN);

Another way to get the type boolean, pass as something that evaluates to true or false like 0 or 1:

http://example.com/foo.php?myVar=0
http://example.com/foo.php?myVar=1

Then cast to boolean:

$hopefullyBool = (bool)$_GET['myVar'];

If you want to pass string true or false then another way:

$hopefullyBool = $_GET['myVar'] == 'true' ? true : false;

But I would say that filter_var with FILTER_VALIDATE_BOOLEAN was meant for this.