Grabbing Category Names
Comments
This trick is so that you can display the category outside of the pM templates. For instance, I use it on my pages inside the <title></title> tag, among other places. It’s also conditional in that nothing will be displayed if you aren’t accessing something through a category link.
> By the way is there a way to get the image title automaticly with the picture.
That completely depends on how you have your weblog and templates set up.
Okay - thx
On wich pages are you putting the grabbing thing?
That I can’t follow
I’m using the “Multi-Entry” version on galleries.php. “Backpacking (Dec 1997)” is the category name and you’ll see that I use it in the <title></title> as well as at the top of the page. If you go to one of the other galleries, you can see how that part of the page changes automatically to reflect the current category.
Once you’re in a gallery, click on a thumbnail. The page that loads in the pop-up is where I use the “Single-Entry” version. Again, I use the category name in the title and at the top of the page and it will change depending on the current category.
(I’m also using the trick on the new “Movie Database” page as well.)
Hi Chris
Now I started all over with exactly your guide, but I can’t get it to work with grabbing the categories name.
The galleries link: http://thebign.dk/galleries
In the page galleries.php with the first code:
<?php include(“pm_inc.php”);?>
<?php
// Check to see if the $id is for a category
if (substr($id, 0,1) == “C”) {
// Get the category ID
$x = explode(“_”,$id);
$cat_id = $x[’1’];
and the rest…..
The next page view.php
<?php include(“pm_inc.php”);?>
<?php
// Grab the last part of the $id
$x = explode(“_”,$id);
$last = $x[(count($x)-1)];
and the rest…
At last I placed the tag:
<?php echo $catname; ?>
In both pages - And nothings is happening.
Hmmmm?
Here is link for all the files as zip
http://thebign.dk/galleries/galleries.zip
Nic
Hi Chris
Now it works on view.php page
How I don’t know, now there is only the galleries.php page left
Nic
Open up galleries.php. Toward the top, you’ll see the line:
$cat_id = $x[’1’];
Make sure you have regular “single-quotes” around the 1. It looks to me like pMachine may have put in special quotes there when it displayed my code.
Yeah
Thanks a lot, now it works.
Nic
Thanks for the great hack, which I looking for long long time. Great work. Thanks again.
Hi Chris
I have now finished my galleri with your toturial guide.
I made a link to your homepage in the the galleri. I have written that the galleri is made with your guide.
The galleri link: http://thebign.dk/galleries
Thanks a lot for your support.
Take care And Have Fun
Nic
Hello Chris,
I’m trying to implement your category grabbing script, but I don’t get it to show the category name.
I put the following code at the top of my page:
<?php include(“pm_inc.php”); ?>
<?php
// Check to see if the $id is for a category
if (substr($id, 0,1) == “C”) {
// Get the category ID
$x = explode(“_”,$id);
$cat_id = $x[’1’];
$db = new DB();
// Query the database to return the category
// name based on the ID
$sql = “SELECT category ” .
“FROM $db_categories ” .
“WHERE id=$cat_id”;
$result = mysql_query($sql);
// Store the category name in $catname
list($catname) = mysql_fetch_row($result);
mysql_free_result($result);
} // END LEAVE THIS
?>
The page in question is at: http://mmjaeger.com/community/links/links.php?id=C0_39_10.
Do you have any idea what could be the problem.
Thank you in advance for your help.
Read comment above, by Chris Curtis @ 01/05/03 10:27pm
mmjaeger,
As Gabriel suggested, check my comment above. Also, did you put the display code anywhere in your page?
<?php echo $catname; ?>
Hello Chris,
I noticed a problem with the single entry category grabbing script!
Let’s say, I’m on a single page with the prev and next link. When I’m entering the single entry page the category name is shown correctly. When I’m clicking on e.g. the next link, it is o.k. as well until I get a picture from another category. It still keeps the old category name then.
Just wanted to let you know about this.
I don’t quite understand why you’re using the list() function when there’s only one result involved? In both cases there will always only be one result.
I’m interested in the reasoning behind this. I would (and actually did when I setup my photolog over the summer) set it up replacing:
list($catname) = mysql_fetch_row($result);
with:
$row = @mysql_fetch_array($result);
$catname = stripslashes($row[‘category’]);
I’m just interested in why you chose to use the list function. 
No particular reason, Lynda. Mostly, I suppose it’s that I’ve gotten used to using that method and it’s just what I used automatically without really even thinking about it.
I don’t think there’s any real advantage to either approach since they’re both just grabbing a value from an array.
I’ve never seen the list() function used in that context before which was why I was asking. It does cut the amount of code down by one line. I’m always interested in learning something new.
Hello chris,
How are you today?
I just discovered a little problem with the grabbing category name on a single-view page.
I’ve limited the number of comments that are shown on the single-view page.
Clicking on the NEXTpage link, the category info is lost, so the category name is not shown anymore on the page.
Any ideas how to fix this.
Thank you
I don’t think there’s anything you can do apart from hack the backend comment display file. There’s simply no way to pass along the category information otherwise.
This trick wasn’t ever meant to work in all cicumstances. It worked for what I needed, but it would be impossible to anticipate all the ways other people might implement it.
Well, if the entry ID is passed along, you can always get the category information. Just do a query using the post ID to grab the category number and then another one using the number to get the name.
Yeah, you’re right, Lynda. My brain’s been really loopy lately, so that didn’t even occur to me. Basically, you’d have to do an if-else.
If the category info is passed in the entry id, then use what I have normally, otherwise you’ll have to do the queries that Lynda suggests.
Hi Chris,
I’m using the catname variable and it works well but on the View All page it throws error. Ideas?
You’d probably need to put an if-else conditional around the <?php echo $catname; ?> so that it only showed if it were not a “view all”.
You could also put the conditional earlier in the script, but that’s a bit more difficult.
I’m Php illiterate could you give an example of the if-else statement
Thanks
The simplest solution would simply be to add this at the top of each of the PHP chunks (i.e. after the <?php and before the code to get the information):
$catname = “All categories”;
Replace the text as you want or even simply have it as $catname = “”;
It works, thanks once again!!
Hi, the multy-entry snippet works, but for single-entry it doesn’t, i think it has something to do that the url’s on the site i’m testing have id’s like that :
id=37_0_8_0_M
(without the usual C), do you have any idea on how to change/repair that?
Regards.
Hey Chris,
Thanks for this. worked like a charm. i added an echo inside the if statement and ran it inline, works perfect.
Chris,
I moved my blog to another server, and now I am getting an error message
Notice: Undefined variable: catname in /home/gladman/public_html/blog/gfd.php on line 200
any ideas?
Tim, take a look at one of my previous comments - specifically, the comments made on 02/25/03.
problem was debug was on.
I’m getting “Fatal error: Cannot instantiate non-existent class: db”
Does this hack only work with certain versions of pMachine? I am on the free 2.1 version.
I was made this code:
<img src=“NASLOVI/
<?php
echo $catname=preg_replace(’/<!—.+?—>/’,’‘,$catname);
?>
.gif” />
it works fine, but something picture not load. when i see the properties of that picture it is /NASLOVI/.gif
when I refresh page picture is loaded.. WHY!? somebody can explain this paradox!?
No, but I can explain to you what paradox means. “A seemingly contradictory statement that may nonetheless be true.” Or an assertion that is apparent to be contradictory. For instance, when someone says that “standing or driving in a car is more tiring that walking all day.”
Thank you, but thats not think which intrested me so much.
:beer: Thanks Chris, another great bit of php from you for us php as a second language folks.
Just wanted to let you know that I implemented your code snippet and it works fine.
Solved a problem I had been sweating over for some time. For some reason the %Ętegory%% variable would not display the category name if I inserted it in my multi-entry or headlines templates.
many thanks
Chris
Greetings from Malaga (Spain). Antonio 
Hi Chris
I do not understand the idea with grabbing the categories name and where to put it
Or my brain can’t follow it
I did this in my photolog template
Weblog Multi-entry Templates (photo2)
Weblog - Master Date Heading (photo2)
TAG: <?php weblog_entries($id,“photo2”); ?>
<h3><b>Galleri: </b>%Ętegory%%</h3>
Then it shows the cagory name.
By the way is there a way to get the image title automaticly with the picture. You know when the mouse is over the picture it shows the alt=“image” so i don´t have to manually to write it.
Nic
By Nic on January 2, 2003 at 02:25pm link