Source could be also accessed from GitHub -> https://github.com/fpetru/WebApiMongoDB.

Problem / solution format brings an easier understanding on how to build things, giving an immediate feedback. Starting from this idea, the blog post will present step by step how to build

a web application to store your ideas in an easy way, adding text notes, either from desktop or mobile, with few characteristics: run fast, save on the fly whatever you write, and be reasonably reliable and secure.

This blog post will implement just the backend, WebApi and the database access, in the most simple way. Next blog post will cover the front end, using Angular. Then, there will be an additional article on how to increase the performance and the security. 

dataObj.users.vahid.email = "info@vmt.ir";

with(dataObj.users.vahid) {
  email = "info@vmt.ir";
}

usersCount = 1;        // Global
var groupsCount = 2;   // Global

(function(){              
  pagesCount = 3;      // Global
  var postsCount = 4;  // Local
})()

outerScope = true
do ->
  innerScope = true

var outerScope;
outerScope = true;
(function() {
  var innerScope;
  return innerScope = true;
})();

package = require('./package')

class Test
  build: ->
    # Overwrites outer variable!
    package = @testPackage.compile()

  testPackage: ->
    package.create()

  class window.Asset
    constructor: ->

function() {}
(window.options || {}).property

function() {}(window.options || {}).property

  <system.webServer>
    <security>
      <authentication>
        <anonymousAuthentication enabled="true" />
        <windowsAuthentication enabled="true" />
      </authentication>
    </security>
  </system.webServer>

{
  "iisSettings": {
    "windowsAuthentication": true,
    "anonymousAuthentication": true,
    "iisExpress": {
      "applicationUrl": "http://localhost:3381/",
      "sslPort": 0
    }
  }
}

<?xml version="1.0" encoding="utf-8"?>
<configuration>
  <system.webServer>
    <handlers>
      <add name="aspNetCore" path="*" verb="*" modules="AspNetCoreModule" resourceType="Unspecified"/>
    </handlers>
    <aspNetCore processPath="%LAUNCHER_PATH%" arguments="%LAUNCHER_ARGS%" 
            stdoutLogEnabled="false" stdoutLogFile=".\logs\stdout" 
            forwardWindowsAuthToken="true"/>
  </system.webServer>
</configuration>

namespace ASPNETCore2WindowsAuthentication
{
    public class Program
    {
        public static void Main(string[] args)
        {
            var host = new WebHostBuilder()
                                     .UseKestrel()
                                     .UseContentRoot(Directory.GetCurrentDirectory())
                                     .UseStartup<Startup>()
                                     .UseHttpSys(options => // Just for local tests without IIS, Or self-hosted scenarios on Windows ...
                                     {
                                         options.Authentication.Schemes =
                                              AuthenticationSchemes.Negotiate | AuthenticationSchemes.NTLM;
                                         options.Authentication.AllowAnonymous = true;
                                         //options.UrlPrefixes.Add("http://+:80/");
                                     })
                                     .Build();
            host.Run();
        }
    }
}

namespace ASPNETCore2WindowsAuthentication
{
    public class Program
    {
        public static void Main(string[] args)
        {
            var host = new WebHostBuilder()
                                     .UseKestrel()
                                     .UseContentRoot(Directory.GetCurrentDirectory())
                                     .UseIISIntegration()
                                     .UseDefaultServiceProvider((context, options) =>
                                     {
                                         options.ValidateScopes = context.HostingEnvironment.IsDevelopment();
                                     })
                                     .UseStartup<Startup>()
                                     .Build();
            host.Run();
        }
    }
}

        public void ConfigureServices(IServiceCollection services)
        {
            services.AddMvc();

            services.Configure<IISOptions>(options =>
            {
                // Sets the HttpContext.User
                // Note: Windows Authentication must also be enabled in IIS for this to work.
                options.AutomaticAuthentication = true;
                options.ForwardClientCertificate = true;
            });
            
            services.AddAuthentication(options =>
            {
                // for both windows and anonymous authentication
                options.DefaultChallengeScheme = IISDefaults.AuthenticationScheme;
            });
        }

        private string authInfo()
        {
            var claims = new StringBuilder();
            if (User.Identity is ClaimsIdentity claimsIdentity)
            {
                claims.Append("Your claims: \n");
                foreach (var claim in claimsIdentity.Claims)
                {
                    claims.Append(claim.Type + ", ");
                    claims.Append(claim.Value + "\n");
                }
            }

            return $"IsAuthenticated: {User.Identity.IsAuthenticated}; Identity.Name: {User.Identity.Name}; WindowsPrincipal: {(User is WindowsPrincipal)}\n{claims}";
        }

namespace ASPNETCore2WindowsAuthentication.Controllers
{
    public class HomeController : Controller
    {
        public IActionResult Index()
        {
            return View();
        }

        [Authorize]
        public IActionResult Windows()
        {
            return Content(authInfo());
        }

        private string authInfo()
        {
            var claims = new StringBuilder();
            if (User.Identity is ClaimsIdentity claimsIdentity)
            {
                claims.Append("Your claims: \n");
                foreach (var claim in claimsIdentity.Claims)
                {
                    claims.Append(claim.Type + ", ");
                    claims.Append(claim.Value + "\n");
                }
            }

            return $"IsAuthenticated: {User.Identity.IsAuthenticated}; Identity.Name: {User.Identity.Name}; WindowsPrincipal: {(User is WindowsPrincipal)}\n{claims}";
        }

        [AllowAnonymous]
        public IActionResult Anonymous()
        {
            return Content(authInfo());
        }

        [Authorize(Roles = "Domain Admins")]
        public IActionResult ForAdmins()
        {
            return Content(authInfo());
        }

        [Authorize(Roles = "Domain Users")]
        public IActionResult ForUsers()
        {
            return Content(authInfo());
        }
    }
}

 dotnet publish

[Authorize(Roles = @"<domain>\<group>")]
//or
[Authorize(Roles = @"<domain>\<group1>,<domain>\<group2>")]

services.AddAuthorization(options =>
{
   options.AddPolicy("RequireWindowsGroupMembership", policy =>
   {
     policy.RequireAuthenticatedUser();
     policy.RequireRole(@"<domain>\<group>"));  
   }
});

 [Authorize(Policy = "RequireWindowsGroupMembership")]

[HttpGet("[action]")]
public IActionResult SomeValue()
{
    if (!User.IsInRole(@"Domain\Group")) return StatusCode(403);
    return Ok("Some Value");
}

    public class ApplicationClaimsTransformation : IClaimsTransformation
    {
        private readonly ILogger<ApplicationClaimsTransformation> _logger;

        public ApplicationClaimsTransformation(ILogger<ApplicationClaimsTransformation> logger)
        {
            _logger = logger;
        }

        public Task<ClaimsPrincipal> TransformAsync(ClaimsPrincipal principal)
        {
            if (!(principal.Identity is ClaimsIdentity identity))
            {
                return Task.FromResult(principal);
            }

            var claims = addExistingUserClaims(identity);
            identity.AddClaims(claims);

            return Task.FromResult(principal);
        }

        private IEnumerable<Claim> addExistingUserClaims(IIdentity identity)
        {
            var claims = new List<Claim>();
            var user = @"VahidPC\Vahid";
            if (identity.Name != user)
            {
                _logger.LogError($"Couldn't find {identity.Name}.");
                return claims;
            }

            claims.Add(new Claim(ClaimTypes.GivenName, user));
            return claims;
        }
    }

            services.AddScoped<IClaimsTransformation, ApplicationClaimsTransformation>();
            services.AddAuthentication(options =>
            {
                // for both windows and anonymous authentication
                options.DefaultChallengeScheme = IISDefaults.AuthenticationScheme;
            });

var userId = User.FindFirstValue(ClaimTypes.NameIdentifier);
var userName = User.FindFirstValue(ClaimTypes.Name);
var userName = User.FindFirstValue(ClaimTypes.GivenName);

// Create a graphics object for drawing.
Graphics gfxCaptchaImage = Graphics.FromImage(bitmap);

gfxCaptchaImage.PageUnit = GraphicsUnit.Pixel;
gfxCaptchaImage.SmoothingMode = SmoothingMode.HighQuality;
gfxCaptchaImage.Clear(Color.White);

// Create a Random Number from 1000 to 9999
int salt = CaptchaHelpers.CreateSalt();

public int CreateSalt()
{
   Random random = new Random();
   return random.Next(1000, 9999);
}

HttpContext.Current.Session["captchastring"] = salt;

string randomString = (salt).NumberToText(Language.Persian);

// Set up the text format.
var format = new StringFormat();
int faLCID = new System.Globalization.CultureInfo("fa-IR").LCID;
format.SetDigitSubstitution(faLCID, StringDigitSubstitute.National);
format.Alignment = StringAlignment.Near;
format.LineAlignment = StringAlignment.Near;
format.FormatFlags = StringFormatFlags.DirectionRightToLeft;

// Font of Captcha and its size
Font font = new Font("Tahoma", 10);

// Create a path for text 
GraphicsPath path = new GraphicsPath();

path.AddString(randomString, 
                font.FontFamily, 
                (int)font.Style, 
                (gfxCaptchaImage.DpiY * font.SizeInPoints / 72), 
                new Rectangle(0, 0, width, height), format);

gfxCaptchaImage.DrawPath(Pens.Navy, path);

//-- using a sin ware distort the image
int distortion = random.Next(-10, 10);
using (Bitmap copy = (Bitmap)bitmap.Clone())
{
          for (int y = 0; y < height; y++)
          {
              for (int x = 0; x < width; x++)
              {
                  int newX = (int)(x + (distortion * Math.Sin(Math.PI * y / 64.0)));
                  int newY = (int)(y + (distortion * Math.Cos(Math.PI * x / 64.0)));
                  if (newX < 0 || newX >= width) newX = 0;
                 if (newY < 0 || newY >= height) newY = 0;
                 bitmap.SetPixel(x, y, copy.GetPixel(newX, newY));
              }
         }
 }

//-- Draw the graphic to the bitmap
gfxCaptchaImage.DrawImage(bitmap, new Point(0, 0));

gfxCaptchaImage.Flush();

HttpResponseBase response = context.HttpContext.Response;
response.ContentType = "image/jpeg";
bitmap.Save(response.OutputStream, ImageFormat.Jpeg);

// Clean up.
font.Dispose();
gfxCaptchaImage.Dispose();
bitmap.Dispose();

public CaptchaImageResult CaptchaImage()
{
     return new CaptchaImageResult();
}

<img src="@Url.Action("CaptchaImage")"/>

[HttpPost]
public ActionResult Index(LogOnModel model)
{
      if (!ModelState.IsValid) return View(model);

      if (model.CaptchaInputText == Session["captchastring"].ToString()) 
             TempData["message"] = "تصویر امنتی را صحیح وارد کرده اید";
      else 
             TempData["message"] = "تصویر امنیتی را اشتباه وارد کرده اید";

      return View();
}

var object1='GC test object 1';
function Test1(){
   var object2='GC test object 2';
   alert (object1+'-' + object2);
}
alert (object1);