Compare multiple values in PHP

I'd like to go from this:

if($var == 3 || $var == 4 || $var == 5 || $var =='string' || $var == '2010-05-16') {
   // execute code here
}

to this:

if($var == (3, 4, 5, 'string', '2010-05-16')) { // execute code here }

Seems very redundant to keep typing $var, and I find that it makes it a bit cumbersome to read. Is there a way in PHP to do simplify it in this way? I read on a post here that when using XQuery you can use the = operator as in $var = (1,2,3,4,5) etc.

Place the values in an array, then use the function in_array() to check if they exist.

$checkVars = array(3, 4, 5, "string", "2010-05-16");
if(in_array($var, $checkVars)){
    // Value is found.
}

http://uk.php.net/manual/en/function.in-array.php

If you need to perform this check very often and you need good performance, don't use a slow array search but use a fast hash table lookup instead:

$vals = array(
    1 => 1,
    2 => 1,
    'Hi' => 1,
);

if (isset($vals[$val])) {
    // go!
}

if (in_array($var, array(3, 4, 5, 'string', '2010-05-16'))) {execute code here }

Or, alternatively, a switch block:

switch ($var) {
    case 3:
    case 4:
    case 5:
    case 'string':
    case '2010-05-16':
        execute code here;
        break;
}

You can use in_array().

if (in_array($var, array(3,4,5,"string","2010-05-16"))) { .... }