${varname} syntax

[wilfordbrimley]

i've seen some scripts using the ${varname} syntax ... what does that mean?

[AIS4U]

wilfordbrimley:

It is not real clear what you are talking about.

All variables in PHP start with the $ sign.

So if you are looking at some PHP script and see something like $MyVar, that means that $MyVar is the name of a variable.

Does this answer your question?

Variables in PHP are represented by a dollar sign followed by the name of the variable. The variable name is case-sensitive.

Maybe the following example will help.

<?php
$var = 'Bob';
$Var = 'Joe';
echo "$var, $Var";      // outputs "Bob, Joe"

$4site = 'not yet';     // invalid; starts with a number
$_4site = 'not yet';    // valid; starts with an underscore
$täyte = 'mansikka';    // valid; 'ä' is (Extended) ASCII 228.
?>

[wilfordbrimley]

no, sorry i should have posted an example...this is from http://us2.php.net/fsockopen

function post($host,$query,$others=''){
   $path=explode('/',$host);
   $host=$path[0];
   unset($path[0]);
   $path='/'.(implode('/',$path));
   $post="POST $path HTTP/1.1\r\nHost: $host\r\nContent-type: application/x-www-form-urlencoded\r\n${others}User-Agent: Mozilla 4.0\r\nContent-length: ".strlen($query)."\r\nConnection: close\r\n\r\n$query";
   $h=fsockopen($host,80);
   fwrite($h,$post);
   for($a=0,$r='';!$a;){
       $b=fread($h,8192);
       $r.=$b;
       $a=(($b=='')?1:0);
   }
   fclose($h);
   return $r;
}

where it says:

$post="POST $path HTTP/1.1\r\nHost: $host\r\nContent-type: application/x-www-form-urlencoded\r\n${others}User-Agent: Mozilla 4.0\r\nContent-length: ".strlen($query)."\r\nConnection: close\r\n\r\n$query";

${others} i couldn't understand that...wasn't sure what the deal was...

[madwormer2]

It can be written like that, or like {$others}.

It's in the braces so that it's not parsed as $othersUser.

If that makes sense to you.

[suntra]

${varname} will simply return the varname variable, but that can only be used between double quotes (").

Outside quotes, like in a variable definition, put single (or double) quotes around vername.

Ex : $newVariable = ${'oldVariable'};

[laserlight]

Outside quotes, like in a variable definition, put single (or double) quotes around vername.

Ex : $newVariable = ${'oldVariable'};

Actually, why not just do:

$newVariable = $oldVariable;

Unless one is using variable variables, the use of braces in variable names outside of strings is redundant.

[suntra]

I was simply showing the possibility...

Maybe I should have wrote something like this :

$myVar1 = 'my value 1';
$myVar2 = 'myVar1';
$myVar3 = ${$myVar2};
$myVar4 = $$myVar2;

So $myVar3 = ${$myVar2} = ${'myVar1'} = $myVar1...

Same thing with $myVar4, but with a different syntax...

[wilfordbrimley]

thanks for the help. makes more sense now.