This tutorial offers a complete insight into linq with ample examples and coding. Microsoft offers tools for both of these languages i. Before we start learning linq language, we must learn some basic knowledge of most used concepts in linq. This tutorial focuses on the linq operations on xml data, that means a dedicated post for linq to xml explanation. On this site you will find practical 101 code samples of how to use linq with both lambda and query expressions. Overview the linq acronym represents the language integrated query programming model birthed by microsoft. I hope this series of linq tutorials will help you in some extent. The acronym linq stands for language integrated query. Linq sum function to sum up collection items tutlane.
About the tutorial the acronym linq stands for language integrated query. These short examples demonstrate how to use a particular linq feature and are listed over here in no particular order. The example uses an integer array as a data source for convenience. Explains the differences between writing queries on an xml tree that is rooted in xelement and writing. Why should we use linq and what are the benefits of.
Basically, what you get is a bunch of standard query operators that can be applied to any ienumerable of type t. Similarly, linq programming returns any of the above mentioned. From time to time, one comes across a bundle that is worth exploring. A sequence is any collection object that implements the ienumerable interface. Linq provides simple and unified mechanism to access different types of data sources such as data structure, xml, and database of microsoft sql server. Net to retrieve data from different sources and formats. The iqueryable interface is used to provide querying capabilities against a specific data source where the type of the data is known. Microsofts query language is fully integrated and offers easy data access from inmemory objects, databases, xml documents, and many more. These tutorials are designed for beginners and professionals who want to learn linq stepbystep. To the best of my knowledge, all code samples on this site work but i cant make any guarantees.
Language integrated query linq provides many tools for working with data. Linq provides an unified query language for query different data sources. Your contribution will go a long way in helping us. Linq to objects, among other implementations, have an input parameter whose type is one of the func family of generic delegates. Sample code solution for linq to object, linq to xml and linq to dataset. The entire tutorial is divided into various topics with subtopics that a beginner can be able to move gradually to more complex topics of linq. Linq tutorials are packed with easy to understand explanations, realworld examples, useful tips, informative notes and points to remember.
The following example shows how the three parts of a query operation are expressed in source code. Standard query operators in linq are actually extension methods for the ienumerable and iqueryable types. Linq tutorials will help you to learn the linq language using topics which go from basic to advanced. A lot of developers over the past few months have requested us for tutorials focusing on linqtoxml. The queryable class includes extension methods for classes that implement iqueryable interface. In addition linq provides on extension methods which helps us to write inline queries on. Linq is a set of extension classes that hook ontopretty much any kind of collection,and they allow us to do some reallyinteresting things with our collections. Traditionally, queries against data are expressed as simple strings without type checking at compile time or intellisense support. In chapter 17, linq everywhere, you will see examples of several other providers, including linq to. Our examples are all compiled and written in visual studio 2010. You can retrieve and save data into sqloracle database with exactly same code. If you observe the above syntaxes, we are summing up the items in num list using linq sum function.
The responsibility of this linq provider is to convert this linq query into a format so that the underlying data source can understand it. Furthermore, you have to learn a different query language for each. Get basic detail about linq, their feature and advantage. The term linq to sql refers to the technology by which we can use linq for access sql databases. Our experts have tried to keep program complete and easy to understand so you can copy the program and run them on your own way. I have been writing some linq tutorials, tips and how tos on my blog and most of these posts contain short snippets that can be used in your project or that demonstrate how to use linq effectively. Linq enables us to query any type of data store sql server, xml documents, objects in memory etc. I searched a lot, but perhaps i am may be miss some links to check. Although i have written a couple of them in the past, i decided to republish these tips in the form of a single post. For example, entity framework api implements iqueryable interface to support linq queries with underlaying.
All linq query operations consist of three distinct actions. This will be specially helpful to web application developers, i guess. These tutorials are broken down into series of related topics, so that you start from a topic which must be understand first, and then gradually learn other features of linq sequentially. It allows for fullnative integration of queries in code, and gives queries firstclass status in a.
The aim of this tutorial is to offer an easy understanding of linq to the beginners who are keen to learn the same. Linq enables the query of data from any type of data source, including databases, xml, list, array and so on. There are over 50 standard query operators available in linq that provide different functionalities like filtering, sorting, grouping, aggregation, concatenation. These delegates use type parameters to define the number and type of input parameters, and the return type. As part of this article, we are going to discuss the following pointers. Linq samples how to use this compilation of 101 samples. For example, we had to write the following code to find all student objects from. In this article, we will explore 24 how do i kind of examples using linq to xml. You will be able to easily readtraverse and adeditdeleteupdate data from xml file with help of linq. On my earlier articles, i have described about working with linq on sql server database, which usually known as linq to sql. Shows how to find a particular element that has an attribute that has a specific value. For some in depth linq code samples, you can also explore the linq examples from microsoft. In the tutorial, we will learn all to basics and advanced linq language and how to use it your own projects with some live examples. Data source using linq as the preceding image shows we can query data from any kind of data source using linq.
Before starting with linq programs, it is best to first understand the nuances of setting up a linq environment. Linqsamples linq 101 query and lambda expression samples. Shows how to find a particular element that has a child element that has a specific value. It makes queries indistinguishable from standard classes, methods, control statements, or other constructions within a language allowing for full. In linq tutorial we covered a topics like linq lambda expressions, aggregate functions, operators. To understand why we should use linq, lets look at some examples. Please read our previous article where we discussed the linq distinct method with examples.
Suppose you want to find list of teenage students from an array of student objects. Net framework, a revolutionary platform to have a diverse kind of applications. Theres a lot of different linq providers for specific types of data for example, theres linq to xml, linq to entities, even linq to sharepoint. I am assuming you are already familiar with basic linq usage. This section provides examples of basic linq to xml queries. Why linq as we have seen in the figure, linq is a technology that is used to query data from any kind of data source. Linq tutorial for beginners and experienced with examples. Language integrated query make query a part of the language component of. Between the actual linq query and underlying data source there is another component called linq provider. So far, with all above listed tutorials, you will learn what we know as linq to sql.
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