Command names¶

Run the complete page example.

A command property and the method it wraps look alike: both are members of the view model, and both can carry a verb such as Save or Search. Give the command property a Command suffix, so a reader can tell which is which without opening the constructor, and give the method it wraps an Impl suffix.

Name the command and its method¶

1. Suffix the command property with Command, and its method with Impl. SaveImplAsync does the work; saveCommand is the property a view binds to.

Enrollment enrollment = new("Robotics Club") { IsEnabled = true };
IObservable<bool> canSave = enrollment.WhenAnyValue(x => x.IsEnabled);

using ReactiveCommand<RxVoid, RxVoid> saveCommand = ReactiveCommand.CreateFromTask(SaveImplAsync, canSave);
using ReactiveCommand<string, RxVoid> searchCommand = ReactiveCommand.CreateFromTask<string, RxVoid>(SearchImplAsync);

_ = await saveCommand.Execute();
_ = await searchCommand.Execute("Robotics");

enrollment.IsEnabled = false;
Console.WriteLine(await saveCommand.CanExecute.FirstAsync());

Saved
Searched for Robotics
False

2. Read CanExecute after the condition changes. saveCommand takes canSave, a stream of enrollment.IsEnabled, as its canExecute argument. Setting IsEnabled to false after the command already ran makes CanExecute read false on the next check. searchCommand takes a string parameter and needs no canExecute argument to run.

Name the property itself after the action it performs, with Command as the suffix: SaveCommand, DeleteCommand, RefreshCommand, SearchCommand. Avoid a property with no suffix, such as Save, and avoid a name that describes the mechanism instead of the action, such as PerformSave.

Naming with source generators¶

ReactiveUI.SourceGenerators, which comes with ReactiveUI, derives the command name for you: a method named Synchronize decorated with [ReactiveCommand] generates a property named SynchronizeCommand. The Impl convention above still applies to whatever method the generated command calls. Reduce boilerplate code covers the attribute.

At a glance¶