Replace variable in template

[error_22]

Hello.

I am currently trying to make myself a simple template engine, for the sake of learning.

I have a table i my db with the following tables:

t_id, t_name, t_content


to fetch a template, all I have to do is to use a simple query in a function:


// this code is placed in a file called templates.php

function template ($template_name) {

$sql = "SELECT `t_content` FROM `templates` WHERE `t_name` = '$template_name'";
$result = mysql_query($sql) or die(mysql_error());
while ($row = mysql_fetch_object($result))
{
echo $row->t_content;
}
}


So wherever I wanna display one of my templates I simply have to include the template file and then put in this simple code:


template(template-name-here);


Nice and easy. My problem is though; in my templates there are several variables, such as $title, $date, $user, $content etc.. To replace these variable with its actual content I use:


str_replace()


but... the content of these variables are called from other tables, in some cases a table called "news" (i have a news script), and in other cases from other tables. So to summarize....Depending on which template i want to use, different tables should be called and replace the variables in the template.

Is there a good way to do this? I cant for the world understand how this would work. Im hoping for some sort of automated script which replaces the right stuff in the right template, calling the right tables etc. just by printing a function with some values or something. Any help would be greatly appreciated!

Thanks in advance
Niklas

[nico_swd]

I wrote a mini-template class a while back. I modified it a bit for your needs. Give it a try if you want.


class swd_template
{

var $variables = array();


function parse($template)
{
extract($this->variables);

eval('$template = stripslashes("'. $this->fetch_template($template) .'");');

echo $template;
}


function fetch_template($template_name)
{
$sql = "SELECT `t_content` FROM `templates` WHERE `t_name` = '$template_name' LIMIT 1";
$result = mysql_query($sql) or die(mysql_error());
$template = mysql_fetch_array($result);

return addslashes($template['t_content']);
}


function assign($key, $value = false)
{
if (is_array($key))
{
$this->variables = array_merge($this->variables, $key);
}
else
{
$this->variables[$key] = $value;
}
}
}


Usage example

$template = new swd_template;

$template->assign(array(
'welcome' => 'hello you', // Replaces $welcome, {$welcome} with "hello you"
'date' => date('dS M Y, H:i:s'), // Replaces $date with the current date
'var' => 'Value' // And $var with value
));

$template->parse('template_name_here');

[error_22]

Just what I was looking for, finally I understand!!

Thank you so much for helping!! =)

[nico_swd]

No problem. If you still have questions on this, just ask.

[error_22]

Ok I actually have one more question.

Your script works perfect, but there's something I dont really know.

I have a a tempalte aclled "index". In the index template theres a variable called "$news". The $news veriable should be replace with a tempalte called "news". That template looks something like this:

<blockquote class="go">
<p>
<h3>$title</h3> - <h5>posted: $date</h5>
</p>
<p>
$content
</p>
</blockquote>

Now.... $title, $date, and $content should be replaced with the content from three columns (with the same names) from a table called "news". I dont know if this is the right way to do it, but I just assumed that I had to have a news template since that one is gonna be looped over and over (total amount of times depends on how many news entries there are). If I put those three variables directly in the index template, everything in there will be looped. How would I go on doing this?

Thank yuo so much for taking the time!

Niklas

[nico_swd]

Well it's just a simple template system. There's no real good way to do it. One of them would be something like this.



$query = mysql_query("SELECT * FROM news... whatever...");

while ($news = mysql_fetch_array($query))
{
$template->assign($news);

$template->parse('news');
}



EDIT:
Assuming the fields in the database are called "news", "date", and "content". Otherwise try this



$query = mysql_query("SELECT * FROM news... whatever...");

while ($news = mysql_fetch_array($query))
{
$template->assign(array(
'title' => $news['title'],
'date' => $news['date'],
'content' => $news['content']
));

$template->parse('news');
}