You can use Split
and get your number like this:
string Location = "1120 - Main Road";
int number = int.Parse(Location.Split()[0]);
This should work if there is no white-space before the number.If there is then use StringSplitOptions.RemoveEmptyEntries
:
int number = int.Parse(Location.Split(new []{ ' ' },
StringSplitOptions.RemoveEmptyEntries)[0]);