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Xiaobian to share with you how to build LINQ framework, I believe most people still do not know how, so share this article for your reference, I hope you have a lot of harvest after reading this article, let's go to understand it together!

Now that LINQ's release has been finalized, it's time to think about how to use it. Keith Farmer even talks about using LINQ to eliminate subclasses. But before we know that, let's take a look at Microsoft's official guide.

In the spirit of the LINQ Building Framework Design Guide, Microsoft has published a LINQ-based Building Framework Design Guide. The LINQ Building Framework Design Guide covers topics such as API design and behavior. Unlike coding guidelines developed by many companies, it does not include design details such as naming patterns and formatting, unless they involve public API libraries.

Most framework design guidelines eventually find ways to integrate with FxCOP. FxCOP is a code analysis tool used by Microsoft and other companies to ensure code consistency.

After an overview, the document describes Extension Methods and generic delegates Func, Action, and Expression. Among the standard caveats given in the guide is a non-namespace conflict guideline--it requires that extension methods not be abused when normal methods can be implemented. Method name conflicts occur when both libraries expose extension methods of the same type. Once this occurs, only one library can be imported, and the other library must have its full name to be referenced.

In the Extending LINQ section, there is a helpful suggestion for naming generic types. A generic type named T always refers to the element items of a collection when the type name is S to refer to a collection containing element items. While this is not mandatory, it at least helps to read built-in methods.

For performance, one recommendation from the guide is that if performance involves computing the total number of elements of a collection, implementing ICollection helps improve performance. When you can only implement IEnumerable, you must traverse the entire collection to get the total number of elements in the collection.

Now, back to Keith Farmer's suggestion to avoid subclasses:

One thing I've been thinking about is reducing the responsibilities of classes to just basic definitions: proper attribute definitions, methods corresponding to attributes, and constructors and type converters.

Then use the extension approach to define the appropriate operations without maintaining the concept of the class as its own entity, so that there is no need to create subtypes (even if subtypes are feasible).

For example, a Node does not need to know the operation of a Graph to work well, or a Graph does not need to know the contents of an IsNetworkRouter.

In this case, a method like Traverse(GraphLink) is a good method definition in Graph, while a method like FindLeastWorkRoute(Node, Node) is defined as an extension method in my opinion because it depends on the implementation details of a particular subtype of GraphLink (i.e., it has an associated Work metric).

Creating a custom subtype just to implement application-specific logic would mess up the class we're interested in (for example, Graph trumps defining Graph and GraphLink at the same time), which can be avoided by extending the method. The LINQ build framework design guidelines are described above.

That's all for the article "How LINQ builds frameworks." Thank you for reading! I believe that everyone has a certain understanding, hope to share the content to help everyone, if you still want to learn more knowledge, welcome to pay attention to the industry information channel!

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