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

What I use to get Phone Numbers without any punctuation...

var phone = "(787) 763-6511";

string.Join("", phone.ToCharArray().Where(Char.IsDigit));

// result: 7877636511