title: C# Web api post parameter always null
body: <p>I'm doing a web API in c# with token, but I need to receive the parameters of postman to my method</p>
  
  <pre><code> [HttpPost, Route("api/cobro/saveEmail")]
      public IHttpActionResult SaveEmailForDiscount([FromBody] string email)
      {
          //do something with e-mail
          return Ok(email);
      }
  </code></pre>
  
  <p>But always the email is null</p>
  
  <p>This is the PostMan request</p>
  
  <pre><code>POST /api/cobro/saveEmail HTTP/1.1
  Host: localhost:53107
  Content-Type: application/x-www-form-urlencoded
  Cache-Control: no-cache
  Postman-Token: 881045b2-0f08-56ac-d345-ffe2f8f87f5e
  
  email=jose%40gm.com
  </code></pre>
  
  <p>This is my Startup class where is all config</p>
  
  <pre><code>    using System;
  using Microsoft.Owin;
  using Owin;
  using Microsoft.Owin.Security.OAuth;
  using System.Web.Http;
  using System.Net.Http.Headers;
  
  [assembly: OwinStartup(typeof(Cobros_BackEnd.Startup))]
  
  namespace Cobros_BackEnd
  {
      public class Startup
      {
          public void Configuration(IAppBuilder app)
          {
  
  
       app.UseCors(Microsoft.Owin.Cors.CorsOptions.AllowAll);
  
          var MyProvider = new AuthorizationServerProvider();
          OAuthAuthorizationServerOptions options = new OAuthAuthorizationServerOptions
          {
  
              AllowInsecureHttp = true,
              TokenEndpointPath = new PathString("/token"),
              AccessTokenExpireTimeSpan = TimeSpan.FromDays(1),
              Provider = MyProvider
          };
          app.UseOAuthAuthorizationServer(options);
          app.UseOAuthBearerAuthentication(new OAuthBearerAuthenticationOptions());
  
          HttpConfiguration config = new HttpConfiguration();
          config.Formatters.JsonFormatter.SupportedMediaTypes
          .Add(new MediaTypeHeaderValue("text/xml"));
  
          //get all users
          config.Routes.MapHttpRoute(
              name: "Users",
              routeTemplate: "api/{controller}/users",
              defaults: new { id = RouteParameter.Optional }
              );
  
  
  
          WebApiConfig.Register(config);
      }
    }
  }
  </code></pre>
  
  <p>I'm using other methods in GET and all work fine, but I need to use this on POST</p>