Visual Studio® 2010 All-in-One For Dummies®

Chapter 7. LINQ

In This Chapter

• Seeing how LINQ differs from SQL

• Creating a simple program to query integers

• Finding active processes

• Creating new object queries

Earlier chapters of this book use SQL Server as a data store and then use the objects that Visual Studio makes available to access the data in the databases. And although that's a large portion of data access techniques, there's more to managing data than database storage. With .NET 3.0, Microsoft took data access to the next level by integrating it into the .NET programming languages. This cool new feature is called Language Integrated Query (LINQ), and it allows you to create powerful queries on not only database storage, but on any collection of data in your programs. Seemingly, every Web site on .NET technologies is talking about it.

LINQ, which is integrated into the newest versions of C# and VB.NET, helps you organize your data structures in a manner similar to how databases organize data. Similar to SQL, you can query program data. For example, say that you have a list of data structures, and you want to find the one that has an ID of 26. You can use LINQ to query the data and find the structure you're looking for.

LINQ isn't just an enhancement to the collection classes. Instead, it's built right into the language. Yup, the querying capabilities are built right into the language. You can run queries against pretty much any kind of data — not just collections. This is one of those language features that you'll wonder how ...