[RESOLVED] include question

yahyac

For some "editing" programs, if you use an include, and then have that same include used on several pages within several different directories, when the editing program includes that page, it will update all links within the included page appropriately.

So for example, if you had an "include" directory in the root of your server (domain) and in the actual include.php page you had a link "../help/help.php", and ASSUMING the "help" directory was also at the root of the server (domain), the link would work properly without any changes, as it would go up one directory (to the root), and would then go down to the help directory.

Some editing programs, when you use a common include in different directory levels, it will automatically update the relative path of the include, to make the links always work.

So if you had that same link "../help/help.php" in the include file, with the "help" directory being at the root of the domain, and even if you used the include page on a page which happened to be X (2, 3, 4, 5, etc.) amount of levels deep into the domain, the relative path would essentially always work.

Bottom line, does the php include work this way? Do relative path links, in an included file, dynamically change depending on what page level the include is brought into? If not, should a person just use absolute paths in the include page.

Thanks.

HeyRay2

This link describes PHP include() behavior:

http://us3.php.net/manual/en/function.include.php

yahyac

I've visited that link, and it is not helping me.

Anyone else?

yahyac

And just to further clarify, here's a current working problem.

First, here's a couple of directories/files for this example:
ROOT/index.php
ROOT/includes/ <-- location of all included files
ROOT/images/ <-- location of all images
ROOT/main/
ROOT/main/sitemap/sitemap.php
ROOT/products/products.php

And here's how I include the specified file on the various pages:
<?php include($_SERVER['DOCUMENT_ROOT'] . "/includes/header.php"); ?>

When i include the header.php file from the index.php, which is in the root, it works fine. Further, when I include the header.php file, into the products.php page, which is located in the products directory (one directory deeper than root), it still works fine.

But here's something just plain weird. When I include the header.php file, into the sitemap.php file, located in the sitemap folder, which in turn is located in the main folder, which in turn is located in the root, it does not work properly.

And what i mean is the following. sitemap.php DOES include the header.php file. That is not the problem. I can see the html showing up. However, the images, which are part of the included file, are not showing up. Instead, you get the typical red box with an X, implying that the image is not there. And when I click on the properties for this "image", it tells me that it is trying to pull the specified image from:
ROOT/main/images/blahblah

BUT THERE IS NO "images" folder under main. So basically, for some reason, when the included file is included into the sitemap.php file, it is not properly referencing the relative image links to their appropriate directory (here, i'm referring the relative links located within the include file).

An included file is often used throughout all pages of a site, which generlly includes several different levels of navigation. So if one uses relative path links in the included file, these links will be broken and cause problems when the included file is used within different levels of the website...UNLESS, php is supposed to not allow this to happen.

Any reasons for this? Perhaps something I am doing wrong?

mediafly

you are obviously trying to access the wrong folder path.

quick fix would be to use the http path to your images or use css.

I always like to use a global site variable for these situations.

$site = "http://www.yourdomain";

<img src="<?=$site;?>/images/image.gif">

Just makes thing less complicated and will work on any level.

yahyac

Obviously, one can always specify absolute paths, whether they be absolute on your system (c:\ paths) or internet paths. BUT, this does not really solve the problem. Rather, this simply avoids the issue.

The goal of a site is to be portable. And one surely wants to develop the site on his/her computer. Using absolute http paths is not the way to do this.

mediafly

yahyac wrote:
Obviously, one can always specify absolute paths, whether they be absolute on your system (c:\ paths) or internet paths. BUT, this does not really solve the problem. Rather, this simply avoids the issue.

The goal of a site is to be portable. And one surely wants to develop the site on his/her computer. Using absolute http paths is not the way to do this.

you can make it portable with the example i gave you

<img src="http://<?=$_SERVER['HTTP_HOST'];?>/images/image.gif" />

yahyac

on a side note, i have never seen html close brackets with the /

ex: <br/> or <img src="blahblah"/>

However, since my viewing of php, I see this often?

Is this something with php? Perhaps just a different way of coding?

bradgrafelman

Has nothing to do with PHP, has everything to do with XHTML.

XHTML requires that every opened tag must be closed. It's obvious that <script> tags need to be closed with an accompanying </script> after the code, but what about <img> and <br> ? Using <img src...></img> would just be silly and more typing, so the /> simply means that the tag has been closed - sort of like opening, defining attributes, and closing an element all in between one set of <>'s.

For a comprehensive list of differences between the HTML 4 that you're used to and this new XHTML 1.0, see this page over at W3C.

yahyac

Well mediafly, that seems to work just fine. I tried it both on my machine and on the domain, and for my machine, it returns "localhost" and on the server, it returns "www.mydomain.com".

So, although this is specifying an absolute path, it is indeed portable.

This is a viable solution. Is there any reason that a person would NOT want to use:
<a href="http://<?=$_SERVER['HTTP_HOST'];?>/blah/blah/blah.php" /> ???

Is there any down fall to this technique? Or is the downfall just that one is using absolute paths? And is there really a problem with that?

bradgrafelman

I would think that using this:

<a href="/blah/blah/blah.php">Link</a>

would be fine.

The problem with your code is that "HTTP_HOST" is a header that the client's browser (should) send. In otherwords, your client's browser is sending data like this to the server:

GET /mypage.html HTTP/1.1
Host: www.yoursite.com
User-Agent: IE Sucks
etc.

This Host: header is required in the HTTP 1.1 protocol, but not required in HTTP 1.0.

So basically, $SERVER['HTTP_HOST'] isn't anywhere near 100% reliable since it depends on data sent by the client. If you really wanted to include the server's domain in the address, I would use $SERVER['SERVER_NAME'] instead - this is configured by the webserver itself.

yahyac

bradgrafelman, is it correct that when your link begins with a backslash, that the link is supposedly starting from the root of the server, as in:

So even if I am 10 levels deep, and want to go only two directories down, would that work?

yahyac

Also, as mentioned, although the <?=$SERVER['HTTP_HOST'];?> concept will work, or as brad said, using <?=$SERVER['SERVER_NAME'];?>, none of these actually deal with the problem I was having with my weird include. They simply sidestep the issue by making all links absolute. Which i guess is fine.

But i was, in my effort to learn, curious as to why my included page was not working properly.

Any ideas? (you will have to reference my 2nd post on this topic for more details)

yahyac

Just to further clarify the question, again here are the example directories in the root of the server:
First, here's a couple of directories/files for this example:
ROOT/index.php
ROOT/includes/ <-- location of all included files
ROOT/images/ <-- location of all images
ROOT/main/
ROOT/main/sitemap/sitemap.php
ROOT/products/products.php

So I have a header.php file, located in the includes directory. This file uses images which are in the "images" directory. So the html code looks as such, <img src="../images/blah.gif">

So while viewing the include, it will look perfect, as in order to grab the image, the instruction says to go back one directory, then go down to images. And sure enough, that is where the images folder is located.

So now, however, lets say i am in the "products" directory, which is TWO levels deep from the server. If in this directory, i have a page, products.php, that includes the header.php file, what happens to those relative links in the header.php file. Because as I just mentioned, they were coded to go up ONE LEVEL (<img src="../images/blah.gif">). So what happens in php. There is my main question. I'm trying to understand how php works. Does php do the background

As mentioned on another thread, I have had too much experience with frontpage, and mainly kept using it casue of the includes. And the included files always fixed the relative links when including a page. So, in this case, when the products.php page would bring in the header.php file, and it would see the images with the aforementioned command, it would, i guess in the background, add another directory "deep" level to the image src commands. So instead of seeing <img src="../images/blah.gif">, one would see <img src="../../images/blah.gif">

So does PHP work in this same way? Does it someone, again, i guess in the background, fix those relative links? If not, what is the purpose of using includes if all the links you use will be broken unless one calls the include from the same depth within the server?

bradgrafelman

No, PHP does not "fix" broken relative links depending on the heiarchy of your folders.

Yes, beginning a link with '/' will signal to the browser that you're starting from the root of the domain, i.e. http://mysite.com/ .

yahyac

bradgrafelman wrote:
No, PHP does not "fix" broken relative links depending on the heiarchy of your folders.

If you are correct, then either:

(a) there is ABSOLUTELY no purpose for using/having PHP includes with regards to handling including a "common" php file across a website

(b) OR, the purpose still exists, BUT, people must know that you can ONLY fulfill this purpose by using absolute links.

bradgrafelman

I wouldn't say that there's no purpose for it... but then again, I wouldn't call myself an expert in PHP anymore than I could say I understand all of the logic required to fulfill such a title. Sorry I'm not much help :/

yahyac

No, on the contrary, you have been helpful.

I'm just still holding on to the hope that someone will come here and post explaining that, yes, you can indeed use relative path links with includes and have none of the files breaking up.

...holding my breath...

yahyac

on a side note, when you explained earlier that one could start a link with a backslash, and that this would essentially start from the root, as follows
<a href="/products/products.php">

Does this method work because of php? Is it the php that recognizes the / and then goes back to the root? Or is that just a common webserver type of command?

First off, it is WORKING! But I ask because within frontpage, which although i am completely handcoding this, i am still doing it in frontpage (why, who knows), but either way, in frontpage, it is not seeing the images when i link to them with the backslash at the beginning of the link. Mind you, I don't really care what frontpage does or does not see, as long as it is valid code and it works. And as mentioned, it is indeed working.

But since frontpage is not seeing the images, perhaps because it does not recognize that type of link", just wondering if it works because the page is a "php" page.

Thanks.

bradgrafelman

No, it's the client's browser. The browser sees the preceding slash and automatically prepends the link with the domain name.

Frontpage doesn't like it because it doesn't realize that the "webroot" isn't actually on the root of your hard drive (which is what the '/' tells Frontpage to do - go to the root).