Example for alternate if

Hi guys,

I have come across this more than once
(condition ? action_if_true: action_if_false
I want to be able to understand it.
Can someone give me a working example?

Thanks,
-Tony

 

normaly we can do this

if (isset($_GET['parameter']))
{
     $param = $_GET['parameter'];
}
else
{
    $param = '';
}

Code (markup):

but the same can be writen on one line as this

$param = isset($_GET['parameter']) ? $_GET['parameter'] : '';

Code (markup):

you can tell it like this
$param IS is variable set $_GET['parameter'] YES WRITE $_GET['parameter'] NO WRITE ''

 

I have another question.
Can this apply to doing something, instead of just setting a variable?
I mean, could you shorten this?

if($mine==false){echo 'User Page';}else{echo 'My User Page';}

PHP:

Thanks,
-Tony

 

echo ($mine == false) ? "user page" : "my user page";

 

Okay...
This?
(assume foo and bar are functions, each with one parameter)

if($mine==false)
{
foo('testvalue');
}
else
{
bar(28);
}

PHP:

Thanks,
-Tony

 

this should be like this but when you want to return a variable to a string use the methods from above.

 

So it cannot be used to select an action, only to select a variable?

-Tony

 

My opinion:

I wouldn't use this method. Code will get more complicated. I like to keep my code as simple as possible and in a format that will work on every server etc.

 

I agree stephan2307, but when you also do alot of things in templates, this will come in handy!

 

Is there a way to spread this over multiple lines? (if I had long strings to echo)

echo ($mine == false) ? "user page" : "my user page";

PHP:

Just so I could see my code better, in a minimized window.

Thanks,
-Tony

 

echo ($mine == false) ? "user\n page" : "my\n user\n page";

PHP:

 

or use <br /> instead of \n

 

I meant spreading the source code out.
For example, could:

$foo=true;
echo ($foo==true) ? "this is such a crazily long string its so long its insane i want to spread it out in my code" : "shortstring";

PHP:

be spread out to:

$foo=true;
echo ($foo==true) ? "this is such a crazily long string its so long its 
 insane i want to spread it out in my code" : "shortstring";

PHP:

without an error?
Because $foo=true, I would want the above snippet to result in:
this is such a crazily long string its so long its insane i want to spread it out in my code
Would that work?

Thanks,
-Tony

 

put () around it

so echo (($foo == true) ? "" : "");

 

So, like this?

echo (($foo==true) ? "this is such a crazily long string its so long its 
 insane i want to spread it out in my code" : "shortstring");

PHP:

That would work fine?

-Tony

 

I assume yes! but have you tried it?

 

Just tried it, works fine!

Thanks,
-Tony

 

If you need more than one line, I'd use HEREDOC to set a variable with that text, then echo the variable. It's neater.

//from the manual
[COLOR=#000000][COLOR=#0000BB]$str [/COLOR][COLOR=#007700]= <<<EOD
[/COLOR][COLOR=#DD0000]Example of string
spanning multiple lines
using heredoc syntax.
[/COLOR][COLOR=#007700]EOD;

[/COLOR][/COLOR]
[FONT=monospace][COLOR=#b1b100]echo[/COLOR] [COLOR=#009900]([/COLOR][COLOR=#000088]$mine[/COLOR] [COLOR=#339933]==[/COLOR] [COLOR=#009900][B]false[/B][/COLOR][COLOR=#009900])[/COLOR] ? [COLOR=#0000ff]"user page"[/COLOR] [COLOR=#339933]:[/COLOR] $str[COLOR=#339933];[/COLOR]
[/FONT]

Code (markup):

 

Why HEREDOC?
Why not just

$str = 'Example of string
spanning multiple lines
using single quotes.';

PHP:

-Tony