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 = " 1 test" string test2 = "test 99" 

How can I do this?

Answer 1

\d+ is the regex for an integer number. So

//System.Text.RegularExpressions.Regex resultString = Regex.Match(subjectString, @"\d+").Value; 

returns a string containing the first occurrence of a number in subjectString.

Int32.Parse(resultString) will then give you the number.