Find and extract a number from a string

Question

I have a requirement to find and extract a number contained within a string.

For example, from these strings:

string test = \"1 test\"
string test1 =         


        

Answer 1

 string input = "Hello 20, I am 30 and he is 40";
 var numbers = Regex.Matches(input, @"\d+").OfType().Select(m => int.Parse(m.Value)).ToArray();