用相应的值替换文本中的变量

Question

Let say I have the following string which I want to send as an email to a customer.

"Hello Mr/Mrs {{Name}}. You have subscribed for {{Service}} at {{Date}}."

And I have an array with the values that should be replaced

array(
    'Name' => $customerName, //or string
    'Service' => $serviceName, //or string
    'Date' => '2015-06-06'
);

I can find all strings between {{..}} with this:

preg_match_all('/\{{(.*?)\}}/',$a,$match);

where $match is an array with values, But I need to replace every match with a corresponding value from an array with values

Note that the array with values contains a lot more values and the number of items in it or the keys sequence is not relevant to number of matches in string.

Answer 1

You can use preg_replace_callback and pass the array with the help of use to the callback function:

$s = "Hello Mr/Mrs {{Name}}. You have subscribed for {{Service}} at {{Date}} {{I_DONT_KNOW_IT}}.";
$arr = array(
    'Name' => "customerName", //or string
    'Service' => "serviceName", //or string
    'Date' => '2015-06-06'
);
echo $res = preg_replace_callback('/{{(.*?)}}/', function($m) use ($arr) {
       return isset($arr[$m[1]]) ? $arr[$m[1]] : $m[0]; // If the key is uknown, just use the match value
    }, $s);
// => Hello Mr/Mrs customerName. You have subscribed for serviceName at 2015-06-06.

See IDEONE demo.

The $m[1] refers to what has been captured by the (.*?). I guess this pattern is sufficient for the current scenario (does not need unrolling as the strings it matches are relatively short).