This is a demo app that shows how to use the "alias any type" feature in C# 12.
The app is a simple console app, that randomly generates valid coordinates (latitude and longitude), then using said coordinates retrieves geo-code metadata related to the coordinates. The coordinates are represented in degrees-minutes-seconds format (including cardinality). And when the app is running, distances between the generated coordinates are calculated and reported as UFO sightings.
From the .NET CLI, use the following command to run the app:
dotnet run --project .\src\Alias.AnyType.csproj
When the app is starts, it will output to the console messaging similar to the following:
After reading the output, press any key to exit for the app to start watching for UFOs 👽.
Press Ctrl + C to exit the app.
The advent of global using syntax in C# 10, and the introduction of alias any type in C# 12, has made it easier to work with types in C#. We're starting to see a common pattern emerge in modern .NET codebases where developers are defining a GlobalUsings.cs file to encapsulate all (or most) using directives into a single file. This demo app follows this pattern:
// Ensures that all types within these namespaces are globally available.
global using Alias.AnyType.Extensions;
global using Alias.AnyType.ResponseModels;
// Expose all static members of math.
global using static System.Math;
// Alias a coordinates object.
global using Coordinates = (double Latitude, double Longitude);
// Alias representation of degrees-minutes-second (DMS).
global using DMS = (int Degree, int Minute, double Second);
// Alias representation of various distances in different units of measure.
global using Distance = (double Meters, double Kilometers, double Miles);
// Alias a stream of coordinates represented as an async enumerable.
global using CoordinateStream = System.Collections.Generic.IAsyncEnumerable<
((double Latitude, double Longitude) Coordinates, Alias.AnyType.ResponseModels.GeoCode GeoCode)>;
// Alias the CTS, making it simply "Signal".
global using Signal = System.Threading.CancellationTokenSource;- View the source:
GlobalUsings.cs
There's several interesting things happening in the GlobalUsings.cs file:
global usingdirectives: Theglobal usingdirective is used to make the types within the specified namespaces globally available. This means that you don't have to include theusingdirective in every file that needs to use the types within the specified namespaces. This is a great way to reduce the amount of boilerplate code in your files.global using staticdirective: Theglobal using staticdirective is used to make all the static members of a type globally available. This means that you don't have to include theusing staticdirective in every file that needs to use the static members of the specified type.global usingalias: Theglobal usingdirective is used to create an alias for a type. This means that you can refer to the type using the alias instead of the full type name. This is a great way to make your code more readable and maintainable.
In addition to defining a GlobalUsings.cs file, you can also globally define using directives in your project file. This is done by adding a Usings element to your project file. Here's an example of how you can define global using directives in your project file:
<Project Sdk="Microsoft.NET.Sdk">
<PropertyGroup>
<OutputType>Exe</OutputType>
<TargetFramework>net8.0</TargetFramework>
<ImplicitUsings>enable</ImplicitUsings>
<Nullable>enable</Nullable>
</PropertyGroup>
<ItemGroup>
<Using Include="System.Console" Static="true" />
<Using Include="System.Net.Http.Json" />
<Using Include="System.Runtime.CompilerServices" />
<Using Include="System.Text" />
<Using Include="System.Text.Json.Serialization" />
<Using Include="System.Text.Json" />
</ItemGroup>
</Project>Be sure to set ImplicitUsings to enable to enable the global using directives in your project file.
The preceding project file defines an ItemGroup that contains various Using elements. Each Using element specifies a using directive that should be globally available in the project. As with the GlobalUsings.cs file, this is a great way to reduce the amount of boilerplate code in your files. And you're able to express static usings, alias usings, and regular usings in the project file.
- View the source:
Alias.AnyType.csproj