Get access token using On Behalf of Flow - Single Sign On Approach

GetOnBehalfAccessTokenAsync.cs

 public async Task<string> GetOnBehalfAccessTokenAsync(string graphScopes, string jwtToken)
        {
            if (jwtToken == null)
            {
                throw new ArgumentNullException(jwtToken, "tokenValidationContext.SecurityToken should be a JWT Token");
            }

            UserAssertion userAssertion = new UserAssertion(jwtToken, "urn:ietf:params:oauth:grant-type:jwt-bearer");
            IEnumerable<string> requestedScopes = graphScopes.Split(new char[] { ' ' }, System.StringSplitOptions.RemoveEmptyEntries).ToList();

            var confidentialClientApp = ConfidentialClientApplicationBuilder.Create(azureAdOptions.Value.ClientId)
                 .WithAuthority(azureAdOptions.Value.Authority)
                 .WithClientSecret(azureAdOptions.Value.ClientSecret)
                 .Build();
            
            var result = await confidentialClientApp.AcquireTokenOnBehalfOf(
                requestedScopes.Except(scopesRequestedByMsalNet),
                userAssertion)
                .ExecuteAsync();
            return result.AccessToken;
        }