Oshadha's Blog

Recently I worked on a project with ASP.NET Core which uses Entity Framework Core. With them, I used a generic repository pattern in the data layer. Repository interface was like below: using System; using System.Collections.Generic; using System.Linq.Expressions; using OnlineSurvey.Models; namespace OnlineSurvey.Data { public interface IRepository<T> where T : BaseEntity { T GetById(int id, params Expression<Func<T, object>>[] includExpressions); void Add(T entity); void Delete(T entity); void Delete(int id); IEnumerable<T> GetAll(params Expression<Func<T, object>>[] includExpressions); IEnumerable<T> Find(Expression<Func<T, bool>> where); int Count(); } } And the implementation was like below: using System; using System.Data.Entity; using System.Data.Entity.Infrastructure; using System.Collections.Generic; using Syste

I got this following error when I hosted my ASP.NET Core 2.2 web API on IIS. An error occurred while starting the application. .NET Core 4.6.27317.07 X64 v4.0.0.0 | Microsoft.AspNetCore.Hosting version 2.2.0-rtm-35687 (Please ignore the version numbers. Just wanted to show the error as it was.) So my first step was to change the  stdoutLogEnabled=true in web.config,  but couldn't find the logs folder. Few mins later I learnt that the  AspNetCoreModule   doesn’t create the logs folder for you by default (Hope they will fixed soon). It logs the error to the Event Viewer which says: Warning: Could not create stdoutLogFile  Path\logs\stdout_xxxxx.log, ErrorCode = -2147024893 . So, I created the the logs folder manually and here I find the real reason why it is failing. Hope this will help you guys.

Currently, I'm working on an ASP.NET CORE 2.2 based project. So, I wanted to host in IIS, which is on Windows Server 2012 R2 system. So, I followed the following steps: Installed the latest version of . NET Core Runtime & Hosting Bundle for Windows. Which you can find in this. Created the application pool with .NET CLR Version: No Manged Code Then created the web application pointing to that application pool. But it was not working, and it started giving me 503 Service Unavailable error. The most important thing is, it was not only for this the web application that I created, but it was also for all the application hosted in this server. When I investigated more I found the following error in Event Viewer: Error logged in Event viewer After looking around for some time, I came to know that the ASP.NET Core/.NET Core: Runtime & Hosting Bundle (latest versions) depends on Microsoft Visual C++ 2015 Redistributable . Even while install

There are number of common design principles that, like design patterns, best practice over the years to build maintainable software. I'm up to describe some widely used design principles though out the post. Following common principle are extracted by the same book that I mentioned before ( Professional ASP.Net Design Patterns - Scott Millet ). Principles are as follows: Keep It Simple Stupid (KISS) One common issue in software programming is over-complicating a solution. So main concern of this principle is keep the code simple but not simplistic. Eventually this will avoid unnecessary complexities. Don't Repeat yourself (DRY) Main concern of this principle is to avoid the repetition. In other words this is all about abstracting out the common functionalities into a single place. Ex: If there is a price calculation method in a system. It should lay in a single place there. Tell Don't Ask The Tell, Don’t Ask principle is closely aligned with encapsulation and the assignin

Hold on!!! Before this please read the common design principle post. After a long time thought of writing a post. Actually these days I'm reading a book which is written by Scott Millet and the name of the book is "Professional ASP.Net Design Patterns". I can guarantee that this book give you a great knowledge on design stuffs. Most of us are bit lazy to read things, so I thought of posting the things that I got form it. This is like the cream of what I got. I'll start it with the S.O.L.I.D design principles: The term S.O.L.I.D. comes from the initial letter of each of the five principles that were collected in the book Agile Principles, Patterns, and Practices in C# by Robert C. Martin, or Uncle Bob to his friends. Simply this is a collection of best practices for object-oriented design. Following will explain all the principles: Single Responsibility Principle (SRP) This principle is closely aligned with a common design principle called Separation of Concerns. It

All the time I was using LINQ on projects I was wondering whether there is a performance difference between query expression and lambda expression. So I decided to dig into it. I wanted to examine MSIL for both of these situations. I wrote small class which has two methods. One is using query expression and the other one is using lambda. I complied this code and got the dll and view the MSIL using ildasm.exe. This following picture will show you the MSIL of GetFirst() method. And this following picture will show you the MSIL of the GetSecond() method. Yes!!! you can see that there is no different between these 2 MSIL. Will there be a performance difference???