Create and Consume JWT Tokens in C#

Introduction

There are plenty of materials on how to manage JWT tokens in C# environment.

But I found most of them are either too complicated for the beginner or outdated.
In this example, we will create and read a JWT token using a simple console app, so we can get a basic idea of how we can use it in any type of projects.

Let's create a simple console project and add these libraries as references:

System.IdentityModel;  
System.Security 

Next, we will need JWT Tokens Package.

Nuget  install-package  "System.IdentityModel.Tokens.Jwt"   

Now we are ready to play with JWT Tokens:

static void Main(string[] args)
       {
           Console.WriteLine("");

           // Define const Key this should be private secret key  stored in some safe place
           string key = "401b09eab3c013d4ca54922bb802bec8fd5318192b0a75f201d8b372742
           9090fb337591abd3e44453b954555b7a0812e1081c39b740293f765eae731f5a65ed1";

           // Create Security key  using private key above:
           // not that latest version of JWT using Microsoft namespace instead of System
           var securityKey = new Microsoft
               .IdentityModel.Tokens.SymmetricSecurityKey(Encoding.UTF8.GetBytes(key));

           // Also note that securityKey length should be >256b
           // so you have to make sure that your private key has a proper length
           //
           var credentials = new Microsoft.IdentityModel.Tokens.SigningCredentials
                             (securityKey, SecurityAlgorithms.HmacSha256Signature);

           //  Finally create a Token
           var header = new JwtHeader(credentials);

           //Some PayLoad that contain information about the  customer
           var payload = new JwtPayload
           {
               { "some ", "hello "},
               { "scope", "http://dummy.com/"},
           };

           //
           var secToken = new JwtSecurityToken(header, payload);
           var handler = new JwtSecurityTokenHandler();

           // Token to String so you can use it in your client
           var tokenString = handler.WriteToken(secToken);

           Console.WriteLine(tokenString);
           Console.WriteLine("Consume Token");


           // And finally when  you received token from client
           // you can  either validate it or try to  read
           var token = handler.ReadJwtToken(tokenString);

           Console.WriteLine(token.Payload.First().Value);

           Console.ReadLine();
       }