Question

I use foreach to loop the array below and then making the order number to be store in the database,

$items_variable = array(
    'page_id',
    'page_content_1',
    'page_content_2',
    'page_content_3',
    'page_content_4',
    ...
);

The code only loop 4 items from the array above (but what if I have these page_content_# increased in the future?)

foreach( $items_variable as $item_variable )
{   
    if (in_array($item_variable, array(
        'page_content_1',
        'page_content_2',
        'page_content_3',
        'page_content_4'
    )))
    {
        if($item_variable == 'page_content_1') $order_in_page = 1;
        if($item_variable == 'page_content_2') $order_in_page = 2;
        if($item_variable == 'page_content_3') $order_in_page = 3;
        if($item_variable == 'page_content_4') $order_in_page = 4;
        ....
        }
}

The current method I have above doesn’t look good to me especially when it comes to the line like this,

if($item_variable == 'page_content_1') $order_in_page = 1;

I will add more lines like this when I have page_content_# increased in the future and the script will look pretty ugly I suppose.

What if I have another type of data with order number (for instance – code_1, code_2, etc)? Then I have copy the code above and change the item name each time – this looks pretty gloomy isn’t!

How can I make it better and dynamic?

Answer 1

Associative array

You can do this:

$items_definitions = array(
    'page_content_1' => 1,
    'page_content_2' => 2,
    'page_content_3' => 3,
    'page_content_4' => 4,
    'page_content_5' => 5,
);

foreach( $items_variable as $item_variable ){ 
    if( isset( $items_definitions[ $item_variable])){
        $order_in_page = $items_definitions[ $item_variable];
    }
    ...
}

Dynamically extracting last part of string

Or do it completely dynamically assuming that it’s always page_content_{$order_in_page}, either with regexp as hackartist suggested or use “oldschool method”:

$prefix = 'page_content_';
foreach( $items_variable as $item_variable ){ 
    if( strncmp( $item_variable, $pregix, strlen( $prefix))){
        continue; // Assume that you don't want to do anything if it doesn't match
    }
    $page = intval( substr( $item_variable, strlen( $prefix)));
    if( !$page){
        continue;
    }
    $order_in_page = $page;
}

I recommend studying examples from intval() documentation 🙂

Switch statement

Php provides switch which allows you to handle many different cases with relatively small amount of code.

foreach( $items_variable as $item_variable ){
    switch( $item_variable){
        case 'page_content_1':
            $order_in_page = 1;
            break;
        case 'page_content_2':
            $order_in_page = 2;
            break;
        case 'page_content_3':
            $order_in_page = 3;
            break;
        ...
        default:
    }
}

I’d however do this only if first two options wouldn’t work out for you (eg. you need to call different function for each case).