how to call Azure AD service in my web form application

Question

I have a WebForms project and some Web Service.My web services are projected by Azure AD. So I need to acquire AD access token in my web from project. But I cannot find any sample about how to integrate Azure AD with web form project in Microsoft official sample. Could someone help me on this?

Answer 1

If you want to call the service protected by Azure AD, you can use OpenId Connect protocol.

For example:

Add a Startup.cs file in your project

using System;
using System.Collections.Generic;
using System.Configuration;
using System.Globalization;
using System.Linq;
using System.Web;
using Owin;
using Microsoft.Owin.Extensions;
using Microsoft.Owin.Security;
using Microsoft.Owin.Security.Cookies;
using Microsoft.Owin.Security.OpenIdConnect;
using Microsoft.Owin.Security.Notifications;
using Microsoft.IdentityModel.Protocols;
using System.Threading.Tasks;
using Microsoft.Identity.Client;
using System.IdentityModel.Tokens.Jwt;
using Microsoft.IdentityModel.Tokens;
using Microsoft.IdentityModel.Protocols.OpenIdConnect;

namespace TestWebForm
{
    public partial class Startup
    {
        private static string clientId = ConfigurationManager.AppSettings["ida:ClientId"];
        private static string aadInstance = EnsureTrailingSlash(ConfigurationManager.AppSettings["ida:AADInstance"]);
        private static string tenantId = ConfigurationManager.AppSettings["ida:TenantId"];
        private static string postLogoutRedirectUri = ConfigurationManager.AppSettings["ida:PostLogoutRedirectUri"];
        private static string redirectUri = postLogoutRedirectUri;
        private static string clientSecret = ConfigurationManager.AppSettings["ida:ClientSecret"];
        string authority = aadInstance + tenantId;

        public void ConfigureAuth(IAppBuilder app)
        {
            app.SetDefaultSignInAsAuthenticationType(CookieAuthenticationDefaults.AuthenticationType);

            app.UseCookieAuthentication(new CookieAuthenticationOptions());

            app.UseOpenIdConnectAuthentication(
                new OpenIdConnectAuthenticationOptions
                {
                    ClientId = clientId,
                    Authority = authority,
                    PostLogoutRedirectUri = postLogoutRedirectUri,

                    Notifications = new OpenIdConnectAuthenticationNotifications()
                    {
                        AuthenticationFailed = (context) =>
                        {
                            return System.Threading.Tasks.Task.FromResult(0);
                        },
                        AuthorizationCodeReceived = OnAuthorizationCodeReceived
                    }

                }
                );


        }
        private Task OnAuthenticationFailed(AuthenticationFailedNotification<OpenIdConnectMessage, OpenIdConnectAuthenticationOptions> context)
        {
            context.HandleResponse();
            context.Response.Redirect("/?errormessage=" + context.Exception.Message);
            return Task.FromResult(0);
        }


        private async Task OnAuthorizationCodeReceived(AuthorizationCodeReceivedNotification notification)
        {
            var idClient = ConfidentialClientApplicationBuilder.Create(clientId)
                .WithRedirectUri(redirectUri)
                .WithClientSecret(clientSecret)
                .Build();

            string[] scopes = { "user.read" };

            var result = await idClient.AcquireTokenByAuthorizationCode(
                scopes, notification.Code).ExecuteAsync();

            GenUtil.token = result.AccessToken;
        }

        private static string EnsureTrailingSlash(string value)
        {
            if (value == null)
            {
                value = string.Empty;
            }

            if (!value.EndsWith("/", StringComparison.Ordinal))
            {
                return value + "/";
            }

            return value;
        }


    }
}

For more details, please refer to Azure AD Authentication in Asp.net web forms web application .