Why doesn't this work?

ChefFrank · 03-08-2006, 06:57 PM

DJMaze was kind enough to give me this code to assist in building a dynamic recipe library (I added the line numbers for clarity):

Code:

1  <html>
2  <body>
3  <table>
4  <tr>
5  <!-- start side navigation
6     <td>
7      <a href="index.php?recipe=1">link 1</a><br/>
8      <a href="index.php?recipe=2">link 2</a><br/>
9      <a href="index.php?recipe=3">link 3</a><br/>
10    </td>
11    <td>
12    <?php
13    // Start the dynamic content/recipes
14
15   if (isset($_GET['recipe']) && preg_match('#[a-z0-9_]#i',$_GET['recipe'])){
16      // cool the visitor wants to see my recipe
17      $recipe = 'recipes/'.$_GET['recipe'].'.html';
18      if (is_file($recipe)) {
19        // the requested recipe exists
20        include($recipe);
21      } else {
22        // the recipe does not exist
23        include('no_recipe.html');
24      }
25    } else {
26        include('index.html');
27    }
28    ?>
29      </td>
30    </tr>
31    </table>
32    </body>
33    </html>

If I follow this correctly, when I load index.php initally, there's no parameter being passed, so the isset($_GET('recipe') should be false, and I should drop down to the include on line 26, which I do - and the page loads fine. Now, if I click on one of the menu items, I should get a match someplace . . .

7 <a href="index.php?irishcoffee">Irish Coffee</a> 
8 <a href="index.php?lambmintsauce">Lamb with Mint Sauce</a> 
9 <a href="index.php?rhubarbcrunch">Rhubarb Crunch</a> 

However, I still see that isset($_GET('recipe') is false and I show my initial page again. (I went through and put a bunch of print statements in the code to follow what's going on).

I am assuming (and we all know what happens when you assume!), that when I load the index.php?irishcoffee, $_GET('recipe') will return the string value "irishcoffee". The preg_match function is validating the field as to content (no strange characters) and I should drop into line 17 and filename validation. Since I have a file recipes/irishcoffee.html, I should hit line 20 and see the text in the file.

Am I interpreting how this works incorrectly? I checked the php documention online for the $_GET, preg_match and isset functions, and don't see why it isn't working.

Thanks in advance - I've only been working with PHP for a day.

Frank

sde · 03-08-2006, 08:23 PM

you are correct.

in your information above, you refer to $_GET['recipe'] as $_GET('recipe'). (note, red is bad

)

you're not using that syntax in your code right? $_GET is an array of the URL variables, and in PHP, brackets after a variable name indicate your are retrieving one element of that array. parenthasis indicate you are calling a function.

ChefFrank · 03-08-2006, 09:05 PM

SDE -

On my screen, it's $_GET['recipe'] - square brackets - in the code - it's parenthesis in my description of the problem - my bad! Now I know!

I understand what you're saying, though - another concept though my thick skull. Array handling is denoted the same way as in C or in ALGOL - with square brackets.

What I am inferring from what you're saying, is that I could call $_GET with multiple variables, such as $_GET['var1', 'var2'] - and I can further infer that PHP does dynamic variable allocation? Not that this fixes my problem, but it's nice to know.

I double checked the code - and even cut and paste the example DJMaze provided into a new file, and had the same problem. Could I have a PHP version problem? I was running V4, and just in case, just updated to V5 - still the same result. So, not a version issue.

Any other idea will be appreciated.

Frank

sde · 03-08-2006, 10:44 PM

index.php?a=foo&b=bar

PHP Code:


			
echo $_GET['a']; // prints: foo

echo $_GET['b']; // prints: bar

at the top of your page, put: echo $_GET['recipe']; to see if you can print what is in the url.

if you really want to know more about arrays in php, you may want to look at this article i wrote a little while back.

DJMaze · 03-09-2006, 04:42 AM

Quote:

Originally Posted by ChefFrank

If I follow this correctly, when I load index.php initally, there's no parameter being passed, so the isset($_GET('recipe') should be false, and I should drop down to the include on line 26, which I do - and the page loads fine. Now, if I click on one of the menu items, I should get a match someplace . . .

7 <a href="index.php?irishcoffee">Irish Coffee</a> 
8 <a href="index.php?lambmintsauce">Lamb with Mint Sauce</a> 
9 <a href="index.php?rhubarbcrunch">Rhubarb Crunch</a>

not "index.php?irishcoffee" but "index.php?page=irishcoffee"

$_GET uses a key and a value (index.php?key=value).

PHP Code:


			
$_GET['key'] = 'value';

there's also a way to only use "index.php?irishcoffee" but just keep it simple for now.

ChefFrank · 03-09-2006, 06:40 AM

DJMaze -

Thanks for that tip - So, now the index table looks like:

<a href="rindex.php?recipe=irishcoffee">Irish Coffee</a> 
<a href="rindex.php?recipe=lambmintsauce">Lamb with Mint Sauce</a> 
<a href="rindex.php?recipe=rhubarbcrunch">Rhubarb Crunch</a> 

And it works like a champ! I just have to do some formatting stuff and it will be good to go.

I see that I could also build a .php script that takes the same input .html file and format it differently through HTML if someone wanted to print just the recipe. Kewl!!!

Thanks a lot. Any recommendations on PHP tutorials?

Frank

ChefFrank · 03-09-2006, 07:27 AM

OK - the sucker's running - when I get some time, I'll pretty it up a bit.

If anyone wants to play with it, it's

http://www.cheffrankonline.com/rindex.php

SDE - now's the time to get that lamb recipe

Frank

DJMaze · 03-09-2006, 07:51 AM

Cool you got it working, the only thing i see in the source is many DOCTYPE and <html>

Normaly a document only allows one of them so get rid of that in your recipes (.html files) since rindex.php handles that.

Another thing i see is � (question marks) this caused by unknown characters like backticks.
These chars are language dependant so you should set the correct Content-Type for processing.
By default Apache uses 'utf8' but you are using something else like iso-8859-1.

Either edit your html files to be in utf8/unicode or set the Content-Type.

A simple unicode supported editor is notepad2 on windows or vim on linux.
http://flos-freeware.ch/notepad2.html

modify Content-Type:
rindex.php

PHP Code:


			
<?php
// headers must be send BEFORE any output (echo, print, etc.)
// see http://www.w3.org/International/O-HTTP-charset
header('Content-Type: text/html; charset=utf-8');
?>
<html>
<body>
<table>

sde · 03-09-2006, 07:57 AM

Quote:

Originally Posted by ChefFrank

OK - the sucker's running - when I get some time, I'll pretty it up a bit.

If anyone wants to play with it, it's

http://www.cheffrankonline.com/rindex.php

SDE - now's the time to get that lamb recipe

Frank

nice, you picked that up pretty quick.

i tried out my new iron skillet last night and i over-cooked some steak after i moved it to the oven. i think i got the feel for it now though. i did 20 minutes in the oven after i seered it, .. i'll try 12 next time.

i've never cooked lamb before, but i think i'm up to it. maybe i'll give it a whril this weekend.

ChefFrank · 03-09-2006, 05:56 PM

Thanks for that tip - the HMTL editor I use 'helpfully' adds things like that if I don't put it in when I close the file. I'll turn that 'helpful' option off and that should clear things up. As I said, I'm experimenting and I have a lot of cleanup to do before I roll it out on the site.

Frank