preg_replace() specific text with value from array

Question

Apologies for the poor title and explanation.

Say I have an array like this:

$myArray = array(
    "name" => "Hello",
    "description" => "World"
);

and some HTML like this:

<h1>{name}</h1>
<p>{description}</p>

Using PHP's preg_replace function (or something else, I don't mind), would it be possible to replace the {} strings with the value in the array?

<h1>Hello</h1>
<p>World</p>

Answer 1

You can do this in vanilla PHP like this:

$str = '<h1>{name}</h1>
<p>{description}</p>';

$myArray = array(
    "name" => "Hello",
    "description" => "World"
);

echo preg_replace_callback('/\{(\w+)}/', function($match) use ($myArray){
    $matched = $match[0];
    $name = $match[1];
    return isset($myArray[$name]) ? $myArray[$name] : $matched;
}, $str);

And here is the result:

<h1>Hello</h1>
<p>World</p>

Or you can use eg ouzo-goodies which implements StrSubstitutor

$str = '<h1>{{name}}</h1>
<p>{{description}}</p>';

$myArray = array(
    "name" => "Hello",
    "description" => "World"
);

$strSubstitutor = new StrSubstitutor($myArray);
$substituted = $strSubstitutor->replace($str);

Answer 2

First, let's construct the regular expression:

$re = implode('|', array_map(function($el) { 
                     return '{' . $el . '}'; 
                   }, array_keys($myArray));

Now we are ready to rock:

$result = preg_replace_callback(
  "/$re/", 
  function($match) use($myArray) { 
    return $myArray[$match[0]]; 
  } , $input
);