Skip to main content

Difference between SkipWhile and Where in linq

Before some time I have written a blog post about the SkipWhile operator and a reader of my blog asked me that we can do the same thing with Where also but there is a difference between this two. So In this post I am going to explain you difference between those two.

Where operator filters a list of collection based on condition. It will filter whole collection while SkipWhile will only skip those elements in list until condition is true and after that it will stop filtering of skipping.Now let’s take an example where we can see the difference between Where and SkipWhile. Following is a code for that.


using System;
using System.Collections.Generic;
using System.Linq;
namespace Linq
{
  class Program
  {
      static void Main(string[] args)
      {
          string[] names = { "Jalpesh", "Jayesh", "Tushar", "Tejas", "Sanjay", "Nijesh","Jemit","Jay" };

          Console.WriteLine("Skipwhile Operator");
          foreach (var name in names.SkipWhile(s => s.ToLower().StartsWith("j")))
          {
              Console.WriteLine(name);
          }
          Console.WriteLine("-----------------------------------");
          Console.WriteLine("Where Operator");
          foreach (var name in names.Where(s => !s.ToLower().StartsWith("j")))
          {
              Console.WriteLine(name);
          }
      }
  }
}


As you can see that in the above code I have a string array called names where I have people’s name as string. Here you can see there are multiple names start with letter “J” in array. Now once we use SkipWhile operator it will skip the elements untill condition is false for first time So it will skip the elements until condition satisfied for the first once you have different condition it will not going skip element even if they are satisfying the condition. While in where it will filter whole collection and print output.

Let’s run above example. Following is a output as expected.

image

That’s it. Hope you like it. Stay tuned for more. Till than happy programming.

Shout it

kick it on DotNetKicks.com

Comments

  1. Great Article related to linq :)

    We can also submit our .net related links on http://www.dotnettechy.com to improve traffic.

    The dotnettechy.com is a community of .Net developers joined together to learn, to teach, to find solutions, to find interview questions and answers, to find .net website / blog collection and to have fun programming. 

    ReplyDelete

Post a Comment

Your feedback is very important to me. Please provide your feedback via putting comments.

Popular posts from this blog

How to create Rest API(Web API) with ASP.NET Core 1.0

Recently Microsoft has released ASP.NET Core 1.0 RC2, I am getting lots of request from readers that about creating Web API. So I thought it will be a good idea to write a blog post about how to create Rest API(Web API) with ASP.NET Core 1.0.

So let’s get started via creating an ASP.NET Core 1.0 Web Application like following.



Once you click on ASP.NET Web Application, It will ask whether you need to create Web Application or Web API application. We are going to Web API so I am going to select Web API Application like following. Please note that in ASP.NET Core 1.0 there is no separate libraries or DLLs required for creating web APIs. This is just a project template.



Now once you click on OK It will create a Web API application with default values controller and program.cs.  As you know Program.cs is now starting point for the ASP.NET Core 1.0 application so It contains all the required configuration and startup items. Following is a code for that.
using System.IO; using Microsoft.Asp…

How to use migration with Entity Framework Core

Entity framework core is  the lightweight, extensible and cross-platform version of Entity Framework. Before some time, Microsoft has Released a new version of Entity Framework RC2. I have written a couple of blog post about Entity framework code first migration earlier for Entity framework 6.0. So there was a couple of request coming for writing a blog post about Entity Framework Core RC2 migration. So I thought it will be a good idea to give an overview how database migration works in Entity Framework Core RC2. This post will cover a basic scenario where we are going to create the database with existing ASP.NET Identity migration and then we are going to create a new model and have that migration applied in the database.

How to use Entity Framework Migrations: Let’s get started, To demonstrate entity framework core migrations, I am going to create a sample asp.net core web application like following.



Once we select asp.net core application it will appear the following dialog.



Now w…

Creating PDF with ASP.Net MVC and RazorPDF

Update: I have written a new blog post about better approach to create a PDF with asp.net mvc- You can find that following location.- A Better Solution to create PDF with Rotativa and ASP.NET MVC
In this post we are going to learn how we can easily create PDF from ASP.Net application with the help of Razor PDF NuGet package.

About Razor PDF:
This NuGet package is created by Al Nyveldt It internally uses ITextSharp an open source PDF convertor library. RazorPDF uses Razor View engine to create iTextXML which is in tern used to produce PDF file. You can get more information about that at below link.

https://www.nuget.org/packages/RazorPDF

Example(Creating PDF with ASP.Net MVC):
So what we are we waiting for ? Let’s create a simple example. To create example first thing we need to a create and ASP.Net MVC application.