www.mysite.com?bar

how to read variables from this kind of link

[wizpl]

I know how to $_GET variable from
www.mysite.com?foo=bar

but how can I get it from
www.mysite.com?bar

I know it is possible, because I know a script which uses this method, but I am not able to reverse engineer it.

[JollyK]

How about $_SERVER['QUERY_STRING']?

JK

[coopster]

An easy way to figure stuff like that out is to dump the variable to the browser. Create yourself a little script that shows you how it works:

myscript.php

<?php 
if (isset($_GET) && $_GET) { 
print '<pre>'; 
print_r($_GET); 
print '</pre>'; 
} 
exit; 
?>

Now open your browser and type this into the address bar:
http://example.com/myscript.php?bar
and you will see that it will print out:

Array 
( 
  [bar] =>  
)

[wizpl]

Thanks, I came up with:

if ($_SERVER['QUERY_STRING']) {
$playlist = $_SERVER['QUERY_STRING'] ;
$playlist = "/demoreel?playlist=$playlist" ;
header("Location:$_SERVER[HTTP_REFERER]$playlist") ;
exit ;
};

and it works of course, however I'd like to learn what the test that was suggested by Coopster tells me.

Array 
( 
 [bar] => 
)

[coopster]

It's telling you that with PHP you are getting an index in your $_GET superglobal with an empty string value. Use var_dump instead of print_r and you will see that it is an empty string value being returned in your 'bar' index:

// using var_dump instead: 
// var_dump($_GET); 
array(1) { 
 ["bar"]=> 
 string(0) "" 
}

In contrast, to really grasp what I was trying to explain, look at what happens when we append to the query string. Let's say the url you use looked like this

http://example.com/myscript.php?bar=foo&baz

We know that QUERY_STRINGs are passed in name=value pairs. Well, in the original example, '?bar' is merely the name, no value associated with it. Now we have added a value and appended a new 'name' but again, no value. print_r and var_dump will show us this:

Array 
( 
  [bar] => foo 
  [baz] =>  
) 
array(2) { 
 ["bar"]=> 
 string(3) "foo" 
 ["baz"]=> 
 string(0) "" 
}

[slade7]

Coopster - would there be some simple way of setting the value of bar as 0 and then using array_flip to turn it around and then extract the value "bar" from the index 0?

I may be way off track...

[wizpl]

hm... and why does this output "Array" instead of Key name?

if ($_GET) {
$playlist = array_keys($_GET) ;
echo $playlist ;
}

[jatar_k]

because array_keys returns an array

[php.net...]

array array_keys ( array input [, mixed search_value [, bool strict]] )

try
if ($_GET) {
$playlist = array_keys($_GET) ;
echo '<pre>';
print_r($playlist);
echo ''</pre>;
}

[Mr_Fern]

I have a function that modifies the get.

function fix_get() {

foreach($_GET as $key => $value) {
if (empty($value))
$_GET[$key] = true;
}

}

It goes through every GET key and if there's no value for the key, it sets to true.

That way I can do things like

if ($_GET['somekey']) {
//do something
}

Although without the function, it's just a matter of doing

if (isset($_GET['somekey'])) {
//do something
}