PHP Switch and adding content to one variable

I'm using this function:

function makeImmunities($data) {
    $immunities = explode(',', $data);
    foreach($immunities as $immunity) {
        switch($immunity) {
            case 'poison':
                $ret .= '<img src="/images/gems/earth.gif"/> ';
            break;
            case 'earth':
                $ret .= '<img src="/images/gems/earth.gif"/> ';
            break;
            case 'paralyze':
                $ret .= '<img src="/images/gems/paralyze.gif"/> ';
            break;
            case 'death':
                $ret .= '<img src="/images/gems/death.gif"/> ';
            break;
            case 'ice':
                $ret .= '<img src="/images/gems/ice.gif"/> ';
            break;
            case 'invisible':
                $ret .= '<img src="/images/gems/invisible.gif"/> ';
            break;
        }
    }
    return $ret;
}

And $ret has .=, so content should be added to itself. But it doesn't. I wan't it to work this way:

$data has an array which looks like thi开发者_Python百科s : 'poison', 'earth', 'death'. And this function returns only first case:

$ret .= '<img src="/images/gems/earth.gif"/> ';

I wan't it too add ALL of the content that $ret has if case is the same as the $immunity.

Switch doesn't work like that you will need to use an if and do something like this:

$options = array(
    'poison' => '<img src="/images/gems/earth.gif"/> ',
    'earth'  => '<img src="/images/gems/earth.gif"/> '
    'etc'    => '...'
);

if(isset($options[$immunity])){
    $ret .= $options[$immunity];
}

The most extensible and easiest I can find (without an if or even a loop)

function makeImmunities($data) {

   $allImmunities = array(
     'poison' => '/images/gems/earth.gif',
     'earth' => '/images/gems/earth.gif',
     'paralyze' => '/images/gems/paralyze.gif',
     'death' => '/images/gems/death.gif',
     'ice' => '/images/gems/ice.gif',
     'invisible' => '/images/gems/invisible.gif',
   );

   $immunities = array_intersect_key($allImmunities, array_flip(explode(',', str_replace(' ','',$data))));

   return implode(' ', array_map(function(&$item, $key) {
      return "<img src=\"{$item}\" alt=\"{$key}\" />";
   }, $immunities, array_keys($immunities)));
}

Exemple:

var_export(makeImmunities('ice,poison,death'));

Output

'<img src="/images/gems/earth.gif" alt="poison" /> <img src="/images/gems/death.gif" alt="death" /> <img src="/images/gems/ice.gif" alt="ice" />'

You wrote that $data contains an array, but from the code it is clear, that it should contain the string, for example $data='earth,ice,poison';. Notice, that there mustn't be any space. By the way, it is good to initialize (with empty string) the $ret variable before foreach.

Just do it like this:

$immunities = explode(',', $data);
foreach($imminities as $key => $value) {
    $ret .= "<img src='/images/gems/{$value}.gif" />";
}
return $ret;

You'll have to check for the immunities though. You could easily add a if clause to inside the foreach, something like

if($value == "earth" || $value == "water" ....)

Pretty simple way to do it.

Update As suggested by Cole, the part inside the if condition could be replaced with a in_array($value, $immunities_supported). I don't know about the efficiency of this though. Remember you also have to add a $immunities_supported = array("earth", "water"); etc with the immunities that are present. (The code below by Cole doesn't work directly though, it's just a concept, since $value is always in $immunities)

Firstly, you need to initialize your "$ret" variable, add "$ret='';" before the "foreach" loop. Use if and elseif.

function makeImmunities($data) {

$ret = ""; //initialise $ret

$immunities = explode(',', $data);

foreach($immunities as $immunity) {

    switch($immunity) {
        case 'poison':
            $ret .= '<img src="/images/gems/earth.gif"/> ';
        break;
        case 'earth':
            $ret .= '<img src="/images/gems/earth.gif"/> ';
        break;
        case 'paralyze':
            $ret .= '<img src="/images/gems/paralyze.gif"/> ';
        break;
        case 'death':
            $ret .= '<img src="/images/gems/death.gif"/> ';
        break;
        case 'ice':
            $ret .= '<img src="/images/gems/ice.gif"/> ';
        break;
        case 'invisible':
            $ret .= '<img src="/images/gems/invisible.gif"/> ';
        break;
    }
    /*
     * creates an array $match with key = immunity of match found e.g poison, death, earth
     * and values equal to <img src="/images/gems/xxxxxx.gif"/> where xxxxxx is the 
     * value for each corresponding image tag. 
     */
    $match[$immunity] = $ret; 
}
return $match;

}

$input = 'poison, earth, death';

$ans = makeImmunities($input); // returns an array

print_r($ans); //prints the array

?>

function makeImmunities($data) {

$ret = ""; //initialise $ret

$immunities = explode(',', $data);  
foreach($immunities as $immunity) {

    switch($immunity) {
        case 'poison':
            $ret .= '<img src="/images/gems/earth.gif"/> ';
        break;
        case 'earth':
            $ret .= '<img src="/images/gems/earth.gif"/> ';
        break;
        case 'paralyze':
            $ret .= '<img src="/images/gems/paralyze.gif"/> ';
        break;
        case 'death':
            $ret .= '<img src="/images/gems/death.gif"/> ';
        break;
        case 'ice':
            $ret .= '<img src="/images/gems/ice.gif"/> ';
        break;
        case 'invisible':
            $ret .= '<img src="/images/gems/invisible.gif"/> ';
        break;
    }

    $match[$immunity] = $ret; 
}
return $match;

}