An event basede ICommand implementation for WPF

RelayCommand.cs

using System;
using System.Windows.Input;

public class RelayCommand : ICommand {
    private readonly Predicate<object> _canExecute;
    private readonly Action<object> _execute;

    public RelayCommand(Action<object> execute, Predicate<object> canExecute = null) {
        _execute = execute ?? throw new ArgumentNullException(nameof(execute));
        _canExecute = canExecute ?? (o => true);
    }

    public event EventHandler CanExecuteChanged {
        add => CommandManager.RequerySuggested += value;
        remove => CommandManager.RequerySuggested -= value;
    }

    public bool CanExecute(object parameter) {
        return _canExecute(parameter);
    }

    public void Execute(object parameter) {
        _execute(parameter);
    }
}