Using classes in namespaces

Each class has a unique name that contains its namespace and class names. For example, the System.Collections.Generic namespace contains a List class. Its name is System.Collections.Generic.List. Anytime you want to use this class you can access it using its full name, but this is not very convenient.

The using directive allows you to add a number of namespaces for the compiler to search when you use classes in the code. This means you can add a using directive to access the System.Collections.Generic namespace, then you can just type List and the compiler will be able to find this for you.

Using — why, when, and how

You are going to need to make use of classes coded within other namespaces in almost every class you create. As a result, you are likely to start every C# file with some using directives that will give you easy access to these classes in your code.

A version of the using directive can give you access to the static methods within a class. We used this in Part 1 when we were calling methods.

In C

Examples

The following examples demonstrate how to code the using directive to access classes within namespaces and static methods within classes.

// Directly access classes within these namespaces
using System.Collections.Generic;
using SplashKitSDK;

// Directly access static methods within these classes
using static System.Console;
using static SplashKitSDK.SplashKit;