C# Anonymous Type Flashcards

Study Notes

Anonymous Type Overview

Anonymous types are types without a defined name, created in C# using the new keyword.
They are stored in implicitly typed variables called var.
Properties in anonymous types are read-only and cannot be modified after initialization.

Characteristics of Anonymous Types

Created with object initializer syntax and can include properties of various data types.
Compiler determines the type for each property based on the assigned value (e.g., string for "First", int for 2, bool for true).
Anonymous types are derived from the System.Object class and are sealed, meaning they cannot be inherited.

Scope and Usage

Anonymous types are local to the method where they are defined and generally cannot be passed to other methods.
They can be passed to methods accepting a dynamic type, although this practice is discouraged.
Output examples can be demonstrated using Console.WriteLine(myAnonymousType.GetType()).

LINQ and Anonymous Types

LINQ’s Select clause generates anonymous types to include specific properties from a data set.
This approach helps optimize memory usage, returning only essential fields instead of entire objects.
Example: In a LINQ query, an anonymous type may include just StudentId and StudentName from a Student class.

Important Notes

An anonymous type is a reference type, meaning its reference is stored on the heap.
All properties in anonymous types are read-only, emphasizing their use for temporary storage of data.
Always use new with object initializer syntax to create anonymous types, and remember their scope is limited to the defining method.

Description

Test your knowledge on C# anonymous types with these flashcards. Explore definitions and explanations to understand how to create and utilize anonymous types in C#. Perfect for beginners and those looking to sharpen their programming skills.