10 "if-else"

[Anon]

Hi. I have a question about timing. I'm drawing a menu and i wander if by putting 10 simple "if-else" is slowing the page and the server.
I know there are other ways, but i have some elements in the menu such as DHTML, that can't be done in another way.

Thanks.

John

[rdhatt]

10? Nah, that's nothing.

If you are checking tha value of the same variable, you might check out 'switch', it provides some syntactic sugar that makes it easier to read.

http://www.php.net/manual/en/control-structures.switch.php

[Anon]

Depending on the server of course :-)
But I agree, 10 if else constructs should not create a lot of load on the server..

[Anon]

I tried switch but there are empty cells i want to keep and some hover DHTML staff. That's why i ended to manual ifs.

John

[[deleted]]

Question: if you must use IF (because no other method gives you what you need) then why do you care about it's performance?
If there is no other way, then you're stuck with it, slow or fast...
:-)

[Anon]

Because i'll skip the fancy staff if performance is a problem. After all i know that too much ifs are not that good but i didn't know the number 🙂

[Anon]

John,

Dude on another forum posted a question asking if lots of echo() functions is CPU intensive...

Well, I told him to measure and let us know...

PHP provides terrific time functions such as microtime()...

You start it

$time1=microtime();

Here will go you 10 if then elses

$time2=microtime();

Then subtract $time1 from $time2 and see the difference in microseconds... You can use time() function to measure seconds, but I doubt that it'll be that slow.

Increase number of if then elses, and test it again. Create a wild process for(;😉; and let it run for 30 seconds, and then test your 10 if then elses and see if the time changed -> and then make your deductions...

If you want to go fancy, formulate a close form formula (something like CPU intensive grows at a rate of N lg N or whatever) so that you can just plug in number of if then elses -> and it'll give you number of seconds or microseconds it'll take to execute under your current computer conditions.

If you'll decide to pull something like that -> let us know about results -> it's always interesting.

Di

[Anon]

Thanks Dmitriy but i'm not yet that deep into PHP 🙂
I just wanted a simple menu 🙂

John

[Anon]

I designed some test questions that have multiple answers that could be correct. I might have as many as 60 to 70 if else statements on one php page and the server flies through that no problem. You probably put a few 1000 before it became a problem.

Something else is making your page slow. Too much graphics or DHTML can do that but 10 if else statements is not your problem.

[Anon]

No. Nothing makes my page slow. It was just a rhetorical question 🙂