Re: Custom function

On 16 February 2011 00:21, Mark Kelly <php@wastedtimes.net> wrote: > Hi. > > On Tuesday 15 Feb 2011 at 23:41 Andre Polykanine wrote: > >> Give it a default (possible empty) value: >> >> function MyFunction($x, $y, $z="") { >> // function goes here >> if (!empty($z)) { >> // The optional parameter is given >> } >> } > > Using an empty string and the empty() function in this way can lead to subtle > and hard to find bugs - for example if $z = 0, the code will not be executed. > Note the list of things that are considered empty: > > http://uk.php.net/manual/en/function.empty.php > > Instead, consider setting the default value for $z to boolean false: > > function MyFunction ($x, $y, $z = FALSE) { >  if ($z) { >    // do stuff with $z >  } > } > > In this way almost any value in $z will trigger the conditional code, > including 0 or an empty string. The exceptions are FALSE and NULL. If you > explicitly need to react to a NULL value, use is_null() to detect it. > > Cheers, > > Mark You also have the option of variable arguments. function foo($x, $y) // 2 mandatory arguments { print_r(func_get_args()); // Show all arguments. } func_get_args() will return an array of arguments to the function. All of them, not just the declared ones. -- Richard Quadling Twitter : EE : Zend @RQuadling : e-e.com/M_248814.html : bit.ly/9O8vFY