So, with C 2. You don't have to use a for loop to find students using different criteria. For example, you can use the same delegate function to find a student whose StudentId is 5 or whose name is Bill, as below:.
The C team felt that they still needed to make the code even more compact and readable. So they introduced the extension method, lambda expression, expression tree, anonymous type and query expression in C 3. You can use these features of C 3. The example below shows how you can use LINQ query with lambda expression to find a particular student s from the student collection. As you can see in the above example, we specify different criteria using LINQ operator and lambda expression in a single statement.
Skip to main content. This browser is no longer supported. Download Microsoft Edge More info. Contents Exit focus mode. Is this page helpful? Yes No. Any additional feedback? Whenever someone talks about data, we tend to only think of the information that is contained in a relational database or in an XML document.
The kind of data access that we had prior to the release of. NET 3. But with the release of. NET 4. For instance, you can query a generic List type containing a few hundred integer values and write a LINQ expression to retrieve the subset that meets your criterion, for example, either even or odd.
The LINQ feature, as you may have gathered, was one of the major differences between. NET LINQ introduces a standard, unified, easy-to-learn approach for querying and modifying data, and can be extended to support potentially any type of data store. NET Framework version 3. Microsoft continued with the LINQ feature with the recent releases of. As I mentioned previously, LINQ introduces the standard and unified concept of querying various types of data sources falling in the range of relational databases, XML documents, and even in-memory data structures.
NET dataset, an in-memory collection, or any other remote or local data source that you have chosen to connect to and access by using LINQ. LINQ bridges the gap and strengthens the connection between relational data and the object-oriented world.
LINQ speeds development time by catching many errors at compile time and including IntelliSense and debugging support. The LINQ assemblies provide all the functionality of accessing various types of data stores under one umbrella. Table Generic Allows users to create strongly typed collections that provide better type safety and performance than nongeneric strongly typed collections LINQ to Objects System.
Figure NET can connect to. Linq namespace can be queried with SQOs. NET functionality can be done by using the System. Linq namespace. This means that you can use LINQ queries not only with user-defined lists, arrays, dictionaries, and so on, but also in conjunction with. For example, you can use the System. Reflection classes to return information about types stored in a specified assembly, and then filter those results using LINQ.
Or you can import text files into enumerable data structures and compare the contents to other files, extract lines or parts of lines, group matching lines from several files into a new collection, and so on. LINQ queries offer three main advantages over traditional foreach loops: They are more concise and readable, especially when filtering multiple conditions. They provide powerful filtering, ordering, and grouping capabilities with a minimum of application code.
They can be ported to other data sources with little or no modification. In general, the more complex the operation you want to perform on the data, the greater the benefit you will realize using LINQ as opposed to traditional iteration techniques. Choose "Windows Forms" project. Right-click the "Form1. Drag a Text Box control onto the form, and position it towards the center of the Form.
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