Question

I know it is possible to use optional arguments as follows:

function doSomething($do, $something = "something") {

}

doSomething("do");
doSomething("do", "nothing");

But suppose you have the following situation:

function doSomething($do, $something = "something", $or = "or", $nothing = "nothing") {

}

doSomething("do", $or=>"and", $nothing=>"something");

So in the above line it would default $something to “something”, even though I am setting values for everything else. I know this is possible in .net – I use it all the time. But I need to do this in PHP if possible.

Can anyone tell me if this is possible? I am altering the Omnistar Affiliate program which I have integrated into Interspire Shopping Cart – so I want to keep a function working as normal for any places where I dont change the call to the function, but in one place (which I am extending) I want to specify additional parameters. I dont want to create another function unless I absolutely have to.

Answer 1

No, in PHP that is not possible as of writing. Use array arguments:

function doSomething($arguments = array()) {
    // set defaults
    $arguments = array_merge(array(
        "argument" => "default value", 
    ), $arguments); 

    var_dump($arguments);
}

Example usage:

doSomething(); // with all defaults, or:
doSomething(array("argument" => "other value"));

When changing an existing method:

//function doSomething($bar, $baz) {
function   doSomething($bar, $baz, $arguments = array()) {
    // $bar and $baz remain in place, old code works
}