PHP if/else differences between return and echo?

Question

I am not understanding this ?quirk? of php at all... as I am looking over other peoples code I see that some people leave out the else statement completely and just place a "return false;" statement.

It seems this trick only works for the return statement and as you can see in the cases below it does not work when echoing text.

This is strange, take case two for example, surely this function is read proceeduraly, so the function will return "true" inside the if statement because the condition is met however when it leaves the if/else statement it should return FALSE because there is no ELSE statement. This DOES NOT happen and the function still returns true.

I can't make sense of this so hopefully someone can explain?

// Case 1
function checkNumber1($number) {
    if ($number === 10) {
        return true;
    } else {
        return false;
    }
}

$number = 10;
var_dump(checkNumber1($number)); // Returns true






// Case 2
function checkNumber2($number) {

    if ($number === 10) {
        return true;
    }
    return false;
}

$number = 10;
echo '<br>';
var_dump(checkNumber2($number)); // Also returns true??






// Case 3
function checkNumber3($number) {
    if ($number === 10) {
        echo 'true' . '<br>';
    } else {
        echo 'false' . '<br>';
    }
}

$number = 10;
echo '<br>';
checkNumber3($number); // Returns true






// Case 4
function checkNumber4($number) {

    if ($number === 10) {
        echo 'true' . '<br>';
    }
    echo 'false' . '<br>';
}

$number = 10;
checkNumber4($number); // Returns true and then false???

In case 2 a return true inside your if statement exits the function. In case 4 echo 'true' in the if statement does not exit the function, so then echo 'false' executes as well. — jszobody
– jszobody, Commented Jun 12, 2016 at 23:08
I think one big difference which is important here is that return ends the function!, while echo does not. So Case 1) 10 == 10 -> If statement -> return true -> function end Case 2) 10 == 10 -> If statement -> return true -> function end (Note: Since the return does end the function it will not execute further) Case 3) 10 == 10 -> If statement -> echo true -> function hits end and stops Case 4) 10 == 10 -> If statement -> echo true -> function executes further -> echo false -> function ends — Rizier123
– Rizier123, Commented Jun 12, 2016 at 23:08
Crumbs you guys are fast, so return exits a function, brilliant, now I understand! Thank you! — Jethro Hazelhurst
– Jethro Hazelhurst, Commented Jun 12, 2016 at 23:09
@JethroHazelhurst You did a good job at testing this and isolating your confusion! Now always when you hit something confusing like this lookup everything (every keyword) in the manual which is involved in this, means: echo and return. — Rizier123
– Rizier123, Commented Jun 12, 2016 at 23:14
Excellent advice, I cant tell you how helpful this is, a small but important thing. Thumbs up! — Jethro Hazelhurst
– Jethro Hazelhurst, Commented Jun 12, 2016 at 23:16

khattam · Accepted Answer · 2016-06-12 23:11:48Z

10

The return statement in a function immediately ends execution of the current function and returns control.

answered Jun 12, 2016 at 23:11

khattam

1,1841 gold badge8 silver badges14 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

PHP if/else differences between return and echo?

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related