// C# implementation of User Authentication
// Include namespace system
using System;
using System.Text.RegularExpressions;
public class GFG
{
public const String NAME = "GEEKSFORGEEKS";
public const String USERNAME = "GEEKS";
public const String PASSWORD = "Geeks@123";
public static bool SignUp(String name, String userName, String password)
{
// Verify password length
if (password.Length < 8 || password.Length > 16)
{
Console.WriteLine("Password must be in range of 8-16 characters.");
return false;
}
Regex regex = new Regex("^(?=.*[a-z])(?=.*[A-Z])(?=.*\\d)(?=.*[@$!%*?&])[A-Za-z\\d@$!%*?&]+");
if (regex.Match(password).Value=="")
{
Console.WriteLine("Password must contains alphanumeric characters and atleast 1 special symbol.");
return false;
}
return true;
}
public static bool Login(String userName, String password)
{
if (userName == USERNAME && password == PASSWORD)
{
return true;
}
Console.WriteLine("Enter Valid Username Or Password!");
return false;
}
public static void Main(String[] args)
{
// Try SignUp With Invalid Password (Length < 8)
Console.WriteLine("User 1 : ");
if (GFG.SignUp(NAME, USERNAME, "Geeks12"))
{
Console.WriteLine("Account Created Successfully.");
}
// Try SignUp With Invalid Password (Excluding Special Symbol)
Console.WriteLine("User 2 : ");
if (GFG.SignUp(NAME, USERNAME, "Geeks123"))
{
Console.WriteLine("Account Created Successfully.");
}
// With Valid Password
Console.WriteLine("User 3 : ");
if (GFG.SignUp(NAME, USERNAME, PASSWORD))
{
Console.WriteLine("Account Created Successfully.");
}
// With Wrong Username Or Password
Console.WriteLine("User 2 : ");
if (GFG.Login(USERNAME, "Geeks123"))
{
Console.WriteLine("Log In Successful.");
}
// With Valid Username And Password
Console.WriteLine("User 3 : ");
if (GFG.Login(USERNAME, PASSWORD))
{
Console.WriteLine("Log In Successful.");
}
}
}
