A closer look
Lets take a look at
eval("\$resultbits .= \"".gettemplate("ResultsBit")."\";");
first. What the eval statement does is evaluate php code as if
you have written it yourself. For example
eval("echo \"thetext\";");
does the same as hard-coding
echo "thetext";
Our code takes advantage of this functionality, by writing it's own php code
for this statement. What's the point, you may ask? Well, just as
echo "hello $name";
would output hello, and the contents of the variable, $name, the
same applies when used within an eval statement. Lets imagine that gettemplate
function returns simply
<td>$data[title]</td>
What ends up being evaluated in the call to the eval statement is
$resultbits .= "<td>$data[title]</td>";
(remembering that we need to escape characters such as $ and " within
the string). PHP then appends <td>$data[title]</td>
to the $resultbits variable, and replaces $data[title]
with its current value. In the same way, PHP replaces all the variables within
our templates with the current value (which, in this instance, has been loaded
from $data=mysql_fetch_array($query).) Our code simply loops through
the information from the database, evaluating the template for each different
value of $data[title] and appends it to $resultbits. Finally, once
the loop is complete, we call another eval statement, this time retrieving the
value from the ResultsPage template, and replacing $pagetitle,$searchquery and
$resultbits with their values in the script. Simple! :-)
And there you have it, your own template based website.