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Showing posts from 2017

Verify database prior to data insertion via EF

Recently, one of my colleague got a requirement on inserting data into database using EF. His issue was, how to verify if the database schema is proper or say all the columns in the tables matches with his POCO entities. Hope few of you must have come across similar scenarios. Here is the quick solution for this. In such scenarios, developers can do the schema compatibility check prior to inserting any data into the columns to ensure that model class still holds good with database tables. bool isModelValid = yourContext. Database . CompatibleWithModel ( true ); In the above method, passing the correct boolean value will do the trick for us. If the parameter value passed is true, then the framework will throw an exception if the schema doesn’t matched with your model class. Isn’t it a useful tip? Happy troubleshooting!!!

Ways to add dependency packages in .NET core

This would be a very short article on how to add dependencies in .Net Core . Well, there are many ways to achieve this. One is via Visual Studio and another way is through command prompt. Let’s quickly have a look.  1) From Visual Studio:  This is the straight forward way for the ones who want to use user interface to add dependencies. Right click on your project/library and get it from Nuget gallery.  2) From Command Prompt:   If you are a command prompt fan, then there itself, you have 2 choices. A) Open command prompt. Navigate to your project directory and simply fire: C:\<Your project directory> dotnet add package Microsoft.AspNetCore   B) Alternative you can go and add the reference directly in .csproj file as shown below: and restore it from command prompt using very simple command: C:\<Your project directory> dotnet restore Happy learning!!!

What and How of Requirement Gathering - Part 3

In continuation to my previous post , I’ll add some more techniques which can be used for information gathering.  Prototyping:   Prototyping allows to gather information by faking the production environment. In this technique, quite a lot of tools can be used to collect information, such as software programs to monitor/record mouse clicks or keystrokes, camera to monitor visual activity, etc.  Basically, what type of tool should be used is solely depend upon what type of information you want to collect. The cost of prototyping might be high because information gathered from this approach can be easily validated with a reason that prototyping is experimental rather than the responses received from users.  Note : Prototyping is preferred in the scenarios where it is impossible to shadow a person. Prototype can help you to get below sort of information:  Use of technologies, tools and applications.  Verification of workflow.  Customer specific quality requiremen

What and How of Requirement Gathering - Part 2

In continuation to my previous post, I’ll add some more techniques which are popularly used for information gathering. Interviewing : While on one hand shadowing provides an effective means to discover what is currently being done in the business, but on the other hand it does not provide all the necessary information. Another flaw of shadowing would be, it is not suitable for getting information about long-term activities that extent weeks or months along with the processes that requires very less or no human intervention. Hence, we can look for other techniques like interviewing. Interviewing someone is the one-on-one meeting between project team and the user. Here quality of information totally depends upon interviewee and the interviewer. The interviewer can ask a wide range of questions as compared to shadowing mechanism. These questions can be from basic information to difficulties to limitations of the system. During the interview process, the interviewee can give some i

What and How of Requirement Gathering - Part 1

This time rather than writing on some technology or solution, I thought to write on one of the important phases of SDLC which is nothing but requirement gathering. To be more specific, this article will be more about collecting information about business requirement. What are the various sources to get and understand most of the portions of any business requirement. It’ very important to understand that, information can be gathered from many standpoints. It can be from Business front, Application front, Operations front, Technology front , and may be many more. So, while gathering information, one should have a clear vision on what kind of information they are looking for. Let’s have a look at few of the well-known categories: B usiness – Goal of business, Service offerings, Products, Financial Structure, etc. Application – Productivity tools, interaction with business application system, Code Modules, etc. Operations – Identify the information’s origin, information’s consump

Generating XML Root Node having colon - via Serialization

Recently I got a requirement to generate an XML on the fly with some defined schema. I know this requirement looks very simple in first sight, but actually it was not. The XML which was to be generated was having a very specific format as it was supposed to be the input for some 3 rd party tool. So, it means, it should be fully compliant with the prescribed XML node structure. Just have a look at the below schema: <sl:RandomWindow xmlns:xsi="" xmlns:sl="" xsi:schemaLocation=" wwRandomWindow.xsd">   <Title>First Window</Title>   <Border>Single</Border> </sl:RandomWindow> Below are the classes I created for serialization purpose: By using the XmlElement and XmlAttribute classes I was able to generate most of the required parts of the XML as shown below:   But the only th

The SDK ‘Microsoft.NET.Sdk.Web’ specified could not be found

If you are working on Visual Studio 2017 with update 3, then you might have come across the error 'The SDK ‘Microsoft.NET.Sdk.Web’ specified could not be found' in netcoreapp1.1 for both web and console. Unfortunately, I also landed up into this situation. So, one straight forward and temporary solution could be to edit the project file manually from Project Sdk = ”Microsoft.NET.Sdk.Web” to Project Sdk = ”Microsoft.NET.Sdk” and re-open the solution. Everything will work fine as expected. So, what are the reasons behind this error? I explored many articles on MSDN forums as well as looked at github link and the primary reasons which are causing this error are: Workstation is still holding an old preview version of CLI 1.0 Installed CLI version is correct but its path is incorrect. Solution : Uninstall all the older versions of CLI with 1.x as SDKs with version 1.x can break things Verify the value of PATH- Open the developer command prompt and verify the value o

Is your client request missing from IIS log?

One can enable IIS logging by going to IIS Manager and checking the Enable logging checkbox. So, it means if IIS logging is enabled, then each and every request made by the client should be showing up in the IIS log. Isn’t it? But by any chance, if the request is not present in IIS log then the most probable reason would be either IIS was not running or may be request was not made. But this statement is not 100% correct. Because whenever any request is made to the server, first it routes through HTTP.SYS then it comes to IIS. So, if anything is not visible under IIS logs, then one can see the logging for HTTP.SYS which is HTTPERR . The most common errors logged here are related to timeout or service unavailability. The next question would be, where these logs are exactly saved? You can find HTTPERR under C:\Windows\System32\LogFiles\HTTPERR

Unable to launch IIS Express from Visual Studio

Recently, while working on one of the web project, I came across a situation which ate up my almost an hour. Concern was, my IIS express was not launching automatically on running my web application from Visual Studio 2015. I tried various solutions like, ran the Visual studio as an Administrator, changed the port, disabled the firewall, reset the IISExpress folder. But no luck :( Then I thought, let's give a try by deleting the temporary folders which were created by Visual Studio and guess what? That worked for me.   The culprit was the .vs folder which was the hidden folder in the project's root directory. One of my colleague checked-in that folder by mistake and as I was fetching the code for the first time, it came on my machine. Actual felon was the .suo file which was inside .vs folder. This .suo file contains user specific settings. Hence same user settings didn’t work for me.   Solution - Deleting .vs folder did the trick :) Happy troubleshooting !!!

Possible Multiple Enumeration of IEnumerable

If you have worked with IEnumerable and using ReSharper , then you may land up into this warning, " Possible Multiple Enumeration of IEnumerable ". So, what this warning is all about? Well, before proceeding further, let’s see how we can store something into IEnumerable object . IEnumerable items = GetAllItems() So, above code itself speaks that items is a variable of type IEnumerable which will hold some values/objects we can iterate through. Now here lies the performance hit, which is also indicated in the form of ReSharper warning. This performance hit may not be significant for a small number of items. But this can be noticed while dealing with a huge number of items. Reason behind this is, whenever you are iterating through items collection, GetAllItems method will be called for the same number of times. Solution : It is always good to materialized the result in a list or array like below: IEnumerable items = GetAllItems().ToList() Once you are done w

.Net Architecture Guidance announced

Few days back, Microsoft announced the draft version of the .NET architecture guidance. This guidance is the combined effort of the Visual Studio team and the Microsoft Developer Division. As of today, it covers only 4 areas: ASP.NET Web applications Azure Cloud Deployment Xamarin Mobile Applications MicroServices and Docker You can find more about this guidance on Microsoft's documentation.

Why normal .NET exception handling doesn't work in WCF?

Errors and exceptions are part of our programming life and WCF is no different. So, when we get errors in WCF, we would like to propagate those errors to our WCF client so that they can accordingly take actions. In order to demonstrate this, let’s go through the code of a simple service: public int Add(int number1, int number2) { return number1 + number2; } public double Divide(int number1, int number2) { return number1 / number2; } Both the above methods will perform some calculation and return the result to the client. Let’s say, now for some reason someone sent 2 nd parameter of Divide method as 0.  What will happen? Definitely code will throw an error or say DivideByZero exception. Isn’t it? Know how to handle this error? Most of the developers will simply decorate Divide method with Try-catch block and throw the exception, similar to our normal .NET exception handling mechanism as shown in be

Which WCF template to be used?

Recently, one of my colleague asked me, which WCF template should I use to create a service? For experienced people, it may be a silly question, but it is one of the common question among beginners, who just entered into the world of services. That’s the motivation who made me write this small post. Well, let’s first have a look at what all templates are available in Visual Studio 2015 for WCF:  The developer can choose any of the above templates as per project need. Let’s go through them one-by-one. WCF Service Library: This template is nothing but a simple service library which uses App.config as its configuration file. WCF Service Application: This template will create a web site which in turn will be hosting a service in it. Here Web.Config will be used to serve configuration settings. WCF Workflow Service Application: This template is useful when you want your workflow to be accessed as a web service. Syndication service Library: This te

DependencyObject in ViewModelBase - Good or Bad?

First of all, a very-very Happy New Year to all my readers. If you are reading this post, then I’m assuming that you have a working experience of WPF using MVVM.  Don’t worry, I’m not going to re-write a huge post on what MVVM is and where to use it? This blog is very small which talks about one of the best practices any developer implementing MVVM should follow. Well, let me provide you the context first. Last week I was going through one of my colleagues’ code and noticed few interesting things in his ViewModelBase class: It was holding few Dependency properties  It was inheriting  DependencyObject  How it sounds to you? Good or … ?  Of course, that is not at all a good practice as ViewModelBase is the base class for all the ViewModels and is not supposed to contain such code. Well, this is not the only reason.  There are many other reasons which are making this implementation a BIG NO.  1 st Reason – A DependencyObject was never meant to be a Source of a bi