.NET正则表达式进入PHP - 发行量获取金额

I am not very familiar in PHP and am kind of stuck grabbing a dollar amount from a sequence of text.

The text is as following:

Shipment price $11 Regular shipment
Shipment price $15 Express shipment 

In .net I would use the following regular expression :

(?<=\$).*(?=Regular)

Which would output : 11 I am only trying to get the price (without dollar sign for "Regular Shipment". Is there anyone who can point me out how to achieve this in php ?

Many thanks in advance !

Its similar in php too however you should use this.

(?<=\$)\S+(?=\s*Regular)

See demo.

https://regex101.com/r/iV6mP5/4

$re = "/(?<=\\$)\\S+(?=\\s*Regular)/i"; 
$str = "Shipment price \$11 Regular shipment
Shipment price \$15 Express shipment "; 

preg_match_all($re, $str, $matches);