Default argument values
PHP allows functions to be defined with default values for arguments. A default value is simply supplied in the argument list using the = sign. Consider the modified heading( ) function described earlier:
function heading($text, $headingLevel = 2)
{
switch ($level)
case 1:
$result = "<h1>" . ucwords($text) . "</h1>";
break;
case 2:
$result = "<h2>" . ucwords($text) . "</h2>";
break;
case 3:
$result = "<h3>" . ucfirst($text) . "</h3>";
break;
default:
$result = "<p><b>" . ucfirst($text) . "</b>";
return($result);
}
$test = "user defined functions";
echo heading($test);
When calls are made to the heading( ) function, the second argument can be omitted, and the default value 2 is assigned to the $headingLevel variable.