and/or

[dennismonsewicz]

How would you say if($var == 2 AND/OR $var == 3)

 

obviously the and/or being the logicals

[ohdang888]

if both need to be true

 

if($var == 2 AND $var == 3){

do this

}

 

if at least one needs to be true:

 

if($var == 2 OR $var == 3){

do this

}

[dennismonsewicz]

hmmm... i got that i was just wondering if there was anyway of doing it within the same if statement

[unidox]

if (($var2 == 2 OR $var == 3) OR ($var == 2 AND $var == 3)) {

 

}

[ag3nt42]

I've been wondering about this myself..

 

Would it also then be possible to give the code choices?

 

Like say if this event happens

 

The code can either run this script

 

or

 

this script

 

or this script

 

which ever one it chooses.

 

Maybe if you matched it up with a math.random sort of thing?

[ohdang888]

no. a script cannot "choose". Its programmed to do a certain thing. Once it finds that it has the permissions to go on, it will, with the first thing.

 

for example, this is pointless:

if (($var == 2 OR $var == 3) OR ($var == 2 AND $var == 3)) {

 

}

 

Main problem here:

a $var cannot equal 2 things at the same time. Unless its in an array, in which case you would use array functions, not "=="

 

[dennismonsewicz]

ok thanks guys!

[.josh]

exactly.  

 

($var == 2 AND $var == 3)

 

would break down because $var cannot equal two things at the same time.  Now if you were to do this:

 

$var = 5;

if(($var > 4) AND ($var < 6)) {

  // condition is true, code here will execute

} elseif (($var > 4) OR ($var < 6)) {

 // condition is true, but will not get executed because the first condition was true

}

 

But you could do this:

 

$var = 10;

if(($var > 4) AND ($var < 6)) {

  // condition is not true, code here won't execute

} elseif (($var > 4) OR ($var < 6)) {

 // condition is true, code will execute

}

 

[LemonInflux]

Quick Question...does AND and OR work now? I always used to use && and ||...Am I living in the past?

[ohdang888]

all of those work

[.josh]

okay && is the same as AND and || is the same as OR.  The only difference between them is the order in which PHP will parse them mathematically.  Kind of like how division will always be performed before multiplication, then addition, then subtraction.  && will take precedence over AND and || will take precedence over OR so if you used both of && and AND in the same condition, && will be evaluated first. 

[LemonInflux]

Ah ok, cheers How long has AND and OR been around then? I'd never heard of them in PHP :S

 

EDIT: well, except in or die(mysql_error()); and similar.

[.josh]

Don't know but I first got into PHP a little over 4 years ago and it was there at least that long ago.

[LemonInflux]

Hah, much longer than I've been doing PHP then (9 months?)

[DarkWater]

Don't know but I first got into PHP a little over 4 years ago and it was there at least that long ago.

 

I've been doing PHP for even longer than that and they've been in it since I started too. =P

[ag3nt42]

you mixed a math.random in there tho it would be able to choose.

 

cuase you could setup a bunch of different cases.. or a bunch of Dynamic cases that use other data

 

and say $action=math.random or something

 

then say

 

switch($action)

 

case '1':

//do this option

break;

case '2':

//do this

break;

 

ect...

[dennismonsewicz]

WOW I didn't realize I had asked a loaded question! ROFL 

[ag3nt42]

lol oh but you have lmao...

 

This is very interesting to me tho.. I wana try and make some kind of application that thinks now.

 

At least thinks alil bit.

[dennismonsewicz]

the question came up when I was doing some server side validation...

[DarkWater]

Well, just to reinforce the point, you can't have an and/or because it logically makes no sense.  It's the equivalent of OR technically. >_>

[.josh]

Well, just to reinforce the point, you can't have an and/or because it logically makes no sense.  It's the equivalent of OR technically. >_>

 

Not necessarily. 

 

OR:

a  b

X  X true

X  O true

O  X true

O  O false

 

yes, if you do a condition with an OR, it will evaluate true if both are true, making it like an AND, but you would not be able to separate the logic.  For instance, if you wanted to do one thing if either one of them would be true (OR), but you wanted to do something else if both were true (AND), you could not do that with an OR by itself.

[DarkWater]

Well, and/or is not a valid logic operator, but in actuality it would function as an OR.  If you wanted to separate it out, that's a different story.  >_>