[SOLVED] Which is more efficient?

[DSGameMaker]

Which is more efficient:

 

if (strlen($name) == 0) {
echo "No name";
}

 

if ($name == "") {
echo "No name";
}

[Mchl]

Probably the second, but unless you're going to loop this thousands of times, the difference will be negligible.

[rhodesa]

inside a loop that ran 1,000,000 times, running on my mid-range pc, the difference was about 0.2 seconds with ($name == "") being that faster one.

 

aka...not a real difference. on a similar note...(empty($name)) was faster by a hair

[DeanWhitehouse]

I would say that the top one is a better way of checking it though, but that is just personal preference.

[DarkWater]

Just as a tip, you'd want to use trim() before checking so that someone doesn't enter only space characters.

[DeanWhitehouse]

The best way, in my opinion, is

<?php
function check_len($check)
{
$check = str_replace(" ","",$check);
$check = trim($check);
$check = strlen($check);
return $check;
}

if (check_len($name) == 0) 
{
echo "No name";
}
?>

[DarkWater]

The str_replace() is pretty useless because trim() would take care of it anyway.

[DeanWhitehouse]

When i have used trim if i enter a few spaces it doesn't work. Unless it has been updated in PHP 5

[DarkWater]

<?php
echo strlen(trim("            ")) . "\n";
?>

 

Says 0 for me.

 

[DeanWhitehouse]

I didn't say it doesn't work, i said when i have used it before it didn't work.

 

Although i think i use to do

if(trim($name) == "")

{

 

}

[DarkWater]

That should still work.

[DeanWhitehouse]

:s i dunno then,lol, i just no i couldn't get it to work properly when learning php so i now use that.

[DSGameMaker]

Wow, didn't expect this much discussion.

 

I'm going to continue using

 

(strlen($name) == 0)

 

I seem to beleive that working with a string uses more memory than a number, and that PHP has to free up a chunk to hold what could be 200 different ASCII characters, when actually, the string is empty. I bet I am wrong, but I don't know.

 

It's good to see the difference is only minimal though

[DarkWater]

When you work with a string literal like that in a boolean statement, it won't actually allocate more than the length that you actually provide.  When you say "", it doesn't actually allocate any new space other than whatever data it has to give to the yylval in Flex and Bison.  The thing is, you should use trim() regardless.  Then you'd have:

strlen(trim($name))

 

And two function calls are much heavier than 1.

[DSGameMaker]

Thanks everyone! Topic Solved.