[RESOLVED] Passing variables from functions back to code

mrgrammar

I am just learning to use functions.

I have a situation where a function is programmed to compute a certain result which is assigned to a variable. Once that variable is defined within the function, I need to use it elsewhere in the code on the page. How do I pass the variable outside the function for use in other places of the code.

Example:

computeresults (1,2,3);
echo $result;

function computeresults($x, $y, $z)
{
$result = $x + $y + $z;
}

I want the page to show the number 6 (which is $result), but it doesn't pass the variable outside the function. How do I do it?

(I didn't know whether to post this question to coding or newbies! lol )

cgraz

You have to 'return' the variable in your function, which basically just means that when that function is called, it will hold that result.

function add( $x, $y )
{
	$result = $x + $y;

return $result;
}

print add( 5, 12 );

Rather than printing, you can create a new variable (lets call it $foo) by saying

$foo = add( 5, 12);

You can also rewrite the function above like this:

function add( $x, $y )
{
	return $x + $y;
}

since there is no point in creating a local variable that you just need to return.

mrgrammar

Thanks! That's exactly what I needed!

cgraz

be sure to mark this resolved if it is.

mrgrammar

I have one more question. What if the function needs to return more than one variable? How do you do that?

cgraz

You'd return an array holding all of the variables.


function( $today )
{
     $result = array();

 if( $today == 'Monday' )
 {
       $result['yesterday'] = 'Sunday';
       $result['today'] = 'Monday';
       $result['tomorrow'] = 'Tuesday';
 }

 // Continue for rest of week

 return $result;
}

This example will return three different values - yesterday, today, and tomorrow.

HTH

mrgrammar

awesome! thanks!

intenz

You can also use the $GLOBALS array...

<?php
function test()
{
	$GLOBALS['foo'] = 'bar';
	$GLOBALS['woo']['key1'] = 'value1';
	$GLOBALS['woo']['key2'] = 'value2';
	$GLOBALS['woo']['key3'] = 'value3';
}

test();
echo $foo . '<br /><br />';
print_r( $woo );

/*
	Will output:

bar

Array
(
	[key1] => value1
	[key2] => value2
	[key3] => value3
)
*/
?>