Fransiscus Setiawan | EV Charging & Azure Solution Architect | Sydney - Page 8 of 19 - Technical Insights: Azure, .NET, Dynamics 365 & EV Charging Architecture

ModelState Errors in MVC through JSON

On May 15, 2012

Normally, when you used HttpPost/Form submission to post the view through the controller then you can have the model validation applied automatically through @Html.ValidationSummary()

But how do you get the ModelState errors through Json? You can still use LINQ to get the model errors from the ModelState and pass it through JSON

Code Snippet

public ActionResult JsonRegister(MemberModel.RegistrationModel model)
        {
            string error = string.Empty;
            if (!ModelState.IsValid)
            {
                IEnumerable<System.Web.Mvc.ModelError> modelerrors = ModelState.SelectMany(x => x.Value.Errors);
                foreach (var modelerror in modelerrors)
                {
                    error += modelerror.ErrorMessage + “\n”;
                }
            }
            return Json(new { success = false, errors = error }, JsonRequestBehavior.AllowGet);
        }

SlideRocket – Cloud

By fransiscuss

On May 14, 2012

In Uncategorized

This is the cloud version of Microsoft Power Point. It is created by the company that I’m working for at the moment. I’m blogging this not because I’m working for them but I’m blogging this based on my personal opinion

It is a powerful web application and It really works as it allows you to use Slide Rocket to share and collaborate your presentation slides with everyone and you don’t need to carry your power point slides file or your laptop. It supports mobile device as well such as an iPad. You just need a connection to the internet

For the standard functionality (Create a presentation slides), it is FREE for life but when you want to use versioning for your presentation, or when you want to have more security control over your presentation, or even to analyse who has accessed your slide and when was it then you need to have monthly subscription. Check it out guys

http://www.sliderocket.com

ps: some guy is using this web application for their resume! and it’s impressive!

http://www.sliderocket.com/blog/2012/05/creative-resume-idea/?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+SliderocketMissionControl+%28SlideRocket+Mission+Control%29

Dependency Injection using Simple Injector Tutorial

By fransiscuss

On May 14, 2012

In .NET

This is a simple tutorial in how to use Dependency Injection using SimpleInjector (You can get this package from NuGet)

In this case, I use SimpleInjector to manage my Data Context – I want my Data Context to be per request (Unit of Work per request). The concept of this dependency Injection is to have a global container where you can resolve your object from

1. Create an extension method to the Simple Injector

Code Snippet

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using SimpleInjector;
using System.Diagnostics;
using System.Linq.Expressions;
///<summary>
/// Extension methods for registering types on a per web request basis.
///</summary>
public static partial class SimpleInjectorPerWebRequestExtensions
{
    [DebuggerStepThrough]
    public static void RegisterPerWebRequest<TService, TImplementation>(
        this Container container)
        where TService : class
        where TImplementation : class, TService
    {
        Func<TService> instanceCreator =
            () => container.GetInstance<TImplementation>();
        container.RegisterPerWebRequest<TService>(instanceCreator);
    }
    [DebuggerStepThrough]
    public static void RegisterPerWebRequest<TService>(
        this Container container,
        Func<TService> instanceCreator) where TService : class
    {
        var creator =
            new PerWebRequestInstanceCreator<TService>(instanceCreator);
        container.Register<TService>(creator.GetInstance);
    }
    [DebuggerStepThrough]
    public static void RegisterPerWebRequest<TConcrete>(this Container container)
        where TConcrete : class
    {
        container.Register<TConcrete>();
        container.ExpressionBuilt += (sender, e) =>
        {
            if (e.RegisteredServiceType == typeof(TConcrete))
            {
                var transientInstanceCreator = Expression.Lambda<Func<TConcrete>>(
                    e.Expression, new ParameterExpression[0]).Compile();
                var creator = new PerWebRequestInstanceCreator<TConcrete>(
                    transientInstanceCreator);
                e.Expression = Expression.Call(Expression.Constant(creator),
                    creator.GetType().GetMethod(“GetInstance”));
            }
        };
    }
    [DebuggerStepThrough]
    public static void DisposeInstance<TService>() where TService : class
    {
        object key = typeof(PerWebRequestInstanceCreator<TService>);
        var instance = HttpContext.Current.Items[key] as IDisposable;
        if (instance != null)
        {
            instance.Dispose();
        }
    }
    private sealed class PerWebRequestInstanceCreator<T> where T : class
    {
        private readonly Func<T> instanceCreator;
        internal PerWebRequestInstanceCreator(Func<T> instanceCreator)
        {
            this.instanceCreator = instanceCreator;
        }
        [DebuggerStepThrough]
        public T GetInstance()
        {
            var context = HttpContext.Current;
            if (context == null)
            {
                // No HttpContext: Let’s create a transient object.
                return this.instanceCreator();
            }
            object key = this.GetType();
            T instance = (T)context.Items[key];
            if (instance == null)
            {
                context.Items[key] = instance = this.instanceCreator();
            }
            return instance;
        }
    }
}

2. Modify Global.asax – The class name will be MvcApplication in MVC Project

Code Snippet

 #region “Dependency Injection”
        private static Container Container;
        public static T GetInstance<T>() where T : class
        {
            return Container.GetInstance<T>();
        }
        protected void RegisterDependency()
        {
            //Create a main containers
            var container = new Container();
            // 2. Configure the container (register)
            container.RegisterPerWebRequest<IUnitOfWork>(() => new UnitOfWork(new PosDataContext()));
            container.Register<ITableRepository, TableRepository>();
            container.Verify();
            Container = container;
        }
        #endregion
        protected void Application_Start()
        {
            AreaRegistration.RegisterAllAreas();
            RegisterGlobalFilters(GlobalFilters.Filters);
            RegisterRoutes(RouteTable.Routes);
            BundleTable.Bundles.RegisterTemplateBundles();
            RegisterDependency();
        }
        protected void Application_EndRequest(object src, EventArgs e)
        {
            ServiceStack.MiniProfiler.Profiler.Stop();
            SimpleInjectorPerWebRequestExtensions.DisposeInstance<IUnitOfWork>();
        }

3. Consume it from the controller – Call the container in the Global.asax to resolve the object (GetInstance function)

Code Snippet

public ActionResult Index()
        {
            ViewBag.Title = “Tables”;
            return View(MvcApplication.GetInstance<IUnitOfWork>().TableRepository.Get(e => e.Active));
        }

IoC Container Benchmarks

By fransiscuss

On May 13, 2012

In .NET

I found this benchmark for different IoC in .NET. Personally I’ve been using Unity, Ninject and SimpleInjector. I like SimpleInjector because it is very simple and surprisingly it is quite fast compared with the rest. Performance is just one of the aspect of IoC but it doesn’t always mean everything

http://www.palmmedia.de/Blog/2011/8/30/ioc-container-benchmark-performance-comparison

http://www.iocbattle.com/

Debugging Knockout

By fransiscuss

On May 10, 2012

In Javascript

I’ve been learning Knockout recently and I found that sometimes it is hard to find out how your View Model is being formed especially when you create the view from Model in MVC

To inspect your view model, you can use firebug console and run below command, this will give you a full navigated View Model and allow you to drill down

console.group(“Dumping view model”);
console.dir(ko.toJS(new JobResultViewModel()));
console.groupEnd();

alternatively you can also put this code in your template

Feel free to let me know if you have any other way to debug

How to Debug WCF Service Issue?

By fransiscuss

On February 27, 2012

In .NET, WCF

1. Change the app.config/web.config of your application that calls the WCF service by adding System.diagnostics detail as below

Code Snippet

 <system.diagnostics>
    <sources>
      <source name=“System.ServiceModel“ switchValue=“Verbose,ActivityTracing“ propagateActivity=“true“>
        <listeners>
          <add type=“System.Diagnostics.DefaultTraceListener” name=“Default“>
            <filter type=“” />
          </add>
          <add name=“ServiceModelTraceListener“>
            <filter type=“” />
          </add>
        </listeners>
      </source>
      <source name=“System.ServiceModel.MessageLogging“ switchValue=“Verbose,ActivityTracing“>
        <listeners>
          <add type=“System.Diagnostics.DefaultTraceListener” name=“Default“>
            <filter type=“” />
          </add>
          <add name=“ServiceModelMessageLoggingListener“>
            <filter type=“” />
          </add>
        </listeners>
      </source>
    </sources>
    <sharedListeners>
      <add initializeData=“MyWCFTraceLog.svclog“
      type=“System.Diagnostics.XmlWriterTraceListener, System, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089“
      name=“ServiceModelTraceListener” traceOutputOptions=“Timestamp“>
        <filter type=“” />
      </add>
      <add initializeData=“MyWCFTraceLog.svclog“
          type=“System.Diagnostics.XmlWriterTraceListener, System, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089“
          name=“ServiceModelMessageLoggingListener” traceOutputOptions=“Timestamp“>
        <filter type=“” />
      </add>
    </sharedListeners>
    <trace autoflush=“true“ />
  </system.diagnostics>

2. Run your application as usual until it throws the error or until the stage where you can reproduce your issue, once you are done, quit your application or take out the diagnostics section from the config file straight away so your log will not be growing too quickly/massively

3. The log file will be called as MyWCFTraceLog.svclog (as we define in the config file) and it will be located on the same folder as the executable – normally it is in the bin folder

4. How to open svclog file? Go to your program files (x86) or program files/Microsoft SDKs/Windows/v7.0A/Bin/SvcTraceViewer.exe

5. SVCTraceViewer will display you the story line of your WCF and it will help you to pinpoint the underlying issue

Delayed Script/Waiting in Javascript

By fransiscuss

On November 30, 2011

In ASP.NET, Javascript

I was struggling in finding out of how to make a simple delegate like in AJAX request through javascript. It takes me a few days to figure this out

Basically the problems are:

-I need to execute a piece code of javascript after getting the ticket from web service function

-The webservice function might not be responding to the first request because it waits for the state of the other external component

-The webservice will give the response when the external component is ready

-The client does not know when the external component is ready, neither the web service. But it wil be ready within 1-5 minutes which again depending external component

Possible Solution:

-Using the setTimeOut(function(){acquireTicket();}, 300000) will cause the application to wait for 5 mins before calling the web service , this approach will slowing down the user experience and waste of time because the external component can be ready earlier than 5 mins

-Using the while loop is not good because it makes the browser freezing while waiting and it will wasting the processing power because of the looping

Recommended Solution:

-Recall the function by itself using setTimeout Function using parameter to indicate whether it should go out of the loop or not

-The web service will be checked for every 2 seconds to check the response from the external component. Once the external component is ready then it will move on to execute the next line of code

–

Access javascript object properties with invalid character

By fransiscuss

On November 17, 2011

In ASP.NET, Javascript

ParseJSON returning you an object from your AJAX Call, the problem that I have is my object properties has invalid character (e.g “#”)

Assuming jsonData is my variable that contains the following information

I’d like to grab the property of “#innerxml”

Normally I can do this to get the property of an object but in this case I can’t due to invalid character

(jQuery.parseJSON(jsonData)[0]).#innerxml

So How do I access an object which has properties where one of the property name is using an invalid character (e.g “#”)

I can access with the following style

(jQuery.parseJSON(jsonData)[0])[‘#innerxml’]

Umbraco Installation in Shared Web Hosting

By fransiscuss

On November 13, 2011

In .NET, Others

I tried to install umbraco in shared webhosting from the control panel but instead the error that I’m getting is

The application could not be installed: Error occured in Web App Gallery module

From my research it seems that there is an error in the Web App Gallery module, some article it says that the Web App Gallery module is out of date. But this is shared web hosting so there is nothing much I can do to fix this. So how to install umbraco manually?

1. Create a blank DB in your SQL Server 2008 for your Umbraco

2. Create a SQL User for the Umbraco DB in the step 1

3. Download umbraco from http://umbraco.codeplex.com

4. Extract the content to the downloaded package to the root of your domain wwwroot folder via FTP

5. Make sure the default website is already created

6. Make sure the .NET framework is being set to .NET 4.0 (Integrated)

7. Run the installation through www.yourdomain.com/install/default.aspx

8. Follow the steps, it will ask you the database name and the database user along the way

9. Once the installation finished, please make sure you delete the install folder for security purpose

Cleanup File name from invalid characters

By fransiscuss

On November 9, 2011

In .NET

I have a function that is used to save a file base on the user input (basically the user can type whichever filename and whichever path) and the code is not handling the invalid filename or path hence what it does is just throwing .NET general exception like below

To fix it I created a new function that basically get the invalid path characters and invalid filename characters from the system and remove invalid character in the input (file name). By doing this the user does not need to replace the character.

If you use Path.GetFileName it will actually remove the illegal character automatically but the way it removes the illegal character is so aggressive

e.g Path.GetFileName(“c:\workflow\Clearance:Photo ID Badge:Access abc-123.ist”) will return Access abc-123.ist

Well this problem itself will give different argument like why do we let people put the garbage character in?and why don’t we give the validation?or the other argument is “why do we need to change the input from the user without letting them knowing it?

236 ”’ <summary>

237 ”’ this function is used to clean up invalid/illegal characters from filename and replace it with blank

238 ”’ </summary>

239 ”’ <param name=”FileName”></param>

240 ”’ <returns></returns>

241 ”’ <remarks></remarks>

242 Private Function CleanFileName(ByVal FileName As String) As String

243 Dim invalid As String = New String(Path.GetInvalidFileNameChars()) + New String(Path.GetInvalidPathChars())

244 Dim originalPath As String = FileName.Substring(0, FileName.LastIndexOf(“\”) + 1)

245 FileName = FileName.Substring(FileName.LastIndexOf(“\”))

246

247 For Each c As Char In invalid

248 FileName = FileName.Replace(c.ToString(), “”)

249 Next

250

251 ‘readd the path

252 FileName = originalPath + FileName

253

254 Return FileName

255 End Function