string.Format,正则表达式+花括号(C#)

string name = "John";
int age = 30;
string result = string.Format("My name is {0} and I am {1} years old.", name, age);

using System.Text.RegularExpressions;

string email = "example@example.com";
Regex regex = new Regex(@"^([\w-\.]+)@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.)|(([\w-]+\.)+))([a-zA-Z]{2,4}|[0-9]{1,3})(\]?)$");
Match match = regex.Match(email);
if (match.Success)
{
    Console.WriteLine("Valid email address.");
}
else
{
    Console.WriteLine("Invalid email address.");
}