Tech learning

WeakReference is a new element added into 4.5 framework, but it was available in Java from the earlier stage only. So, this article could be useful for .Net, Java, and Android as well. What is it? It is nothing more than a class but what special about is to interact with Garbage Collector in a certain way which could help out in optimization. Scenario We all know that static members are created and shared throughout the application and life cycle by maintaining only single instance. Possibly it can useful in cases where data need to be frequently accessed but what about those that doesn't need to be frequently accessed all times. Those data might be resource hungry data so static or some kind of caching mechanism is required. Storing something in static members or caching increases memory footprint for the application. This is once situation, but there might be other situation as well. WeekReference is a technique to hook up member with Garbage collector to retrieve actual ...

It can be bit tricky to configure both Ninject and Asp.Net Identity UserManager if some value is expected from DI to configure UserManager. We will look into configuring both and also use OwinContext to get UserManager. As usual, all configuration need to be done on Startup.cs. It is just a convention but can be used with different name, the important thing is to decorate class with following attribute to make it Owin start-up: [assembly: OwinStartup(typeof(MyProject.Web.Startup))] Ninject configuration Configuring Ninject kernel through method which would be used to register under Owin. Startup.cs public IKernel CreateKernel() { var kernel = new StandardKernel(); try { //kernel.Bind<IHttpModule>().To<HttpApplicationInitializationHttpModule>(); // TODO: Put any other injection which are required. return kernel; } catch { kernel.Dispose(); thro...

Audit logs can be tedious task if done manually, also developer might miss to update audit log implementation on certain level. The codes would be repeated on all places if not centralized. There are many approach available to maintain change history of model/table. Like having single history table and manage all changes of all models in same table. We may maintain in same table with some flags and JSON data for change list. We will look for maintaining history table based on each required data models with minimum effort and performance. To reduce code, I am going to use T4 to generate history models automatically based on original model. Also we are going to take care of Artificial type values. Step 1 - Create a custom attribute to mark model that history need to be maintained. /// <summary> /// Attribute to maintain history table /// </summary> [AttributeUsage(AttributeTargets.Class)] public class ManageHistoryAttribute : Attribute ...

The actual process to make DataSourceRequest compatible with AutoMapper was explained in my previous post  Kendo MVC Grid DataSourceRequest with AutoMapper , where we had created custom model binder attribute and in that property names were changed as data models. In this post we will be looking into using AutoMapper's Queryable extension to retrieve the results based on selected columns. When  Mapper.Map<RoleViewModel>(data)  is called it retrieves all column values from table. The Queryable extension provides a way to retrieve only selected columns from table. In this particular case based on properties of  RoleViewModel . The previous approach that we implemented is perfect as far as this article ( 3 Tips for Using Telerik Data Access and AutoMapper ) is concern about performance where it states: While this functionality allows you avoid writing explicit projection in to your LINQ query it has the same fatal flaw as doing so - it prevents the qu...

With evolution of ASP.Net MVC there are lot of inbuilt feature came and evolved with time. One of those is Authorization and Custom Authorization. The in-built function is sufficient enough to handle anonymous user restriction, user based on there name, specific roles for user with just single class AuthorizeAttribute . To implement we need to decorate attribute on any given class, action based on need. Example: [Authorize] public ActionResult Test() { } By just providing  Authorize  attribute anonymous user are restricted. It has Roles  and Users  property parameters to restrict access based on certain role or user which can accept multiple values by comma separated as string format. In one of the situation, I got chance to built an authorization where roles keep changing. Administrator can add new role, delete any role or modify existing role. In that situation we cannot map roles with codes. So, there were two way to achieve by creating group ...