How can I exit a if block if a certain condition is met?
I tried using break but it doesn't work:
if($bla):
$bla = get_bla();
if(empty($bla)) break;
do($bla);
endif;
it says: Fatal error: Cannot break/continue 1 level in...
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2check stackoverflow.com/questions/7468836/… for more opinions (:AgelessEssence– AgelessEssence2011-11-15 01:33:20 +00:00Commented Nov 15, 2011 at 1:33
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12 Answers
In PHP 5.3 you can use goto
if($bla):
$bla = get_bla();
if(empty($bla)) goto end;
do($bla);
endif;
end:
But personally I think that's an ugly solution.
3 Comments
doc_id
Why ugly? It would be useful in certain situations for sure. Vote up!
tschoffelen
May I ask why the people behind PHP introduced it in 2009? They could have chosen to not introduce it at all. I agree that it feels very DOS-like to me (not in the good way), but it can come in handy for sure.
Petter Pettersson
It still has a purpose, exiting out of nested loops for example.
Why not just turn it around.
if($bla):
$bla = get_bla();
if(!empty($bla)) {
do($bla);
}
endif;
That way it will only run your code if $bla isn't empty.. That's kinda the point with if-statements
3 Comments
doc_id
Your answer solves the problem but doesn't answer the question "How can I exit an if block", it worth to note if it's ever possible.
Sondre
@rahmanisback Like you say, it solves the problem so I don't really see what's wrong with my answer. If you just look one answer down you'll see that the question is answered. When I posted my answer there were already several posts answering this, so what I did was provide an actual solution. You can't break an if statement and if you ever need to do so you're using it wrong.
Jacob Raccuia
It solved my problem! I was doing the same thing, trying to exit when I could rearrange. I see the merit in actually answering the question, but if the question is using an improper method or not practical, it should be noted. Thanks!
You can't break if statements, only loops like for or while.
If this if is in a function, use 'return'.
Comments
I cant believe no one have post this solution yet (writing it in my PHP style):
if($bla){do{
$bla = get_bla();
if(empty($bla)) break;
do($bla);
}while(false);}
Complexity still O(1)
answered Dec 20, 2013 at 18:14
Marcos Fernandez Ramos
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1 Comment
Marki
Wow. But it's still totally perverted... We have goto at our disposal, we can even use an include() and return from there, but we can't just quit the if block...
Try this
do {
if($bla) {
$bla = get_bla();
if (empty($bla)) {
break;
}
do($bla);
}
/* You can do more comparisions here */
} while (0);
Comments
You can't.
You could put the whole thing into a function from which you can return.
Otherwise, you'll have to change the logic and include another if block.
if($bla):
$bla = get_bla();
if(!empty($bla)):
do($bla);
endif;
endif;
Comments
For me it helps to have an escape marker in case the code needs to exit between blocks if you don't mind having an if statement in another.
$exit = FALSE;
if(!$exit){
if($data["param1"] == cond1){
//do something and continue
}
else{
//do something
$exit = TRUE;
}
}
if(!$exit){
if($data["param2"] == cond2){
//do something and continue
}
else{
//do something
$exit = TRUE;
}
}
{...}
If you keep placing conditional statements around each block, it will not execute any other blocks after you set $exit to true. You can name the variable $continue and revert its roles if that makes more sense to you.
it works easier if you have no else statements.
$exit = FALSE;
if($bla):
$bla = get_bla();
if(empty($bla)) $exit = TRUE;
if(!$exit)do($bla);
endif;
Comments
Strictly speaking, we can't leave if-block prematurely, but sometimes it's really needed. break can be used only inside loops and switch-block. But we can place if in a loop. So, answer of Marcos Fernandez Ramos is probably the most appropriate. Here is just slightly nicer variant.
do if ()
{
...
if () break;
...
} while (false);
Comments
If you really want a statement from which you can break, you could use a while statement:
while ($bla) {
$bla = get_bla();
if (!$bla) {
break;
}
do($bla);
// Maybe some more code...
// Do not forget to break out of the while loop!
break;
}
This is a good way of avoiding many nested if statements (which can maybe be avoided in many cases), but do be careful to break the loop.
Comments
if your condition is a test against a single variable, then the switch statement is a much better solution and you can easily break out:
switch ($var_to_check) { // equivalent to if ($var_to_check==$value_against)
case $value_against:
...
if ($something_wrong) { break; } // early exit from if
...
break; // regular break
default: // equivalent to else
...
} // end of switch (or if)
... // after the tests
It only works for single test checks. Has the advantage of handling a bunch of else ifs.
Comments
Just replace IF with WHILE and add break; at the end of the new while statement and anywhere in middle too.
Comments
You can create a function for the contains of your IF block. For example
if($bla):
doSomething();
endif;
Then you can simply use RETURN
function doSomething() {
$bla = get_bla();
if(empty($bla)) return;
do($bla);
}
It's looking more clearly than multiply IF statements
