PHP Function and variables stored in a string in a database - php

Question

I need to store data within a database, when I get the data from the database I need functions and variables in the string to be worked out as such.
Example
$str = "<p>Dear {$this->name},</p>"
I then store this in the database, and when I retrieve the string and run it through
eval("\$detail= \"$detail\";");
then the variable gets populated with the name. This is exactly what I needed and works fine.
The problem is I want to run a function with this variable as the parameter.
example. I would like to ucwords the variable.
I have tried:
$str = "<p>Dear {ucwords($this->name)},</p>" //just echoed {ucword(->name)},
$str = "<p>Dear {ucwords($this->name)},</p>" //Fatal error: Function name must be a string,
Am I going in the right direction?
Is this at all possible?

Answer 1

You don't need to keep PHP code in database. This is a bad practice and also can lead to security vulnerabilities.
Instead store in database string like this:
<p>Dear [name],</p>
And when you retrieve it you can just do:
$stringFromDb = str_replace("[name]", $this->name, $stringFromDb);
or
$stringFromDb = str_replace("[name]", ucwords($this->name), $stringFromDb);
Other common approach is to use sprintf. So you need to store in database string with %s as placeholders for values.
Example:
<p>Dear %s,</p>
and replace with
$stringFromDb = sprintf($stringFromDb, ucwords($this->name));

Answer 2

What you seem to be looking for is a simple templating language.
It's been a long while since I've written PHP (and I suddenly remember why...), but here's something I whipped up.
It should support both objects ($a->name) and arrays ($a["name"]) as input objects.
You can add new filters (name -> function name mapping) in $valid_filters.
$valid_filters = array("title" => "ucfirst", "upper" => "strtoupper");
function _apply_template_helper($match) {
global $_apply_template_data, $valid_filters;
$var = $match[1];
$filter = $valid_filters[trim($match[2], ':')];
$value = is_array($_apply_template_data) ? $_apply_template_data[$var] : $_apply_template_data->$var;
if($filter && !empty($value)) $value = call_user_func($filter, $value);
return !empty($value) ? $value : $match[0];
}
function apply_template($template, $data) {
global $_apply_template_data;
$_apply_template_data = $data;
$result = preg_replace_callback('/\{\{(.+?)(:.+?)?\}\}/', "_apply_template_helper", $template);
$_apply_template_data = null;
return $result;
}
How to use it:
$template = "Hello {{name:title}}, you have been selected to win {{amount}}, {{salutation:upper}}";
echo apply_template($template, array("name"=>"john", "amount" => '$500,000', "salutation" => "congratulations"));
The result:
Hello John, you have been selected to win $500,000, CONGRATULATIONS

Answer 3

I have found the following works,
If i contain the function within the class itself then it can be called using the following code
<p>Dear {\$this->properCase(\$this->rl_account->name)},</p>
But i would like to be able to do this now without having the database have the code as Alex Amiryan mentions earlier.