WPFの定番コード集その1。Command

Command.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Input;

namespace TemplateApp.ViewModel
{
    public class Command : ICommand
    {
        public event EventHandler CanExecuteChanged;

        private bool isExecutable;

        public bool IsExecutable
        {
            get { return isExecutable; }
            set { isExecutable = value; CanExecuteChanged?.Invoke(this, new EventArgs()); }
        }

        private Action<object> commandAction;

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

        public void Execute(object parameter)
        {
            this.commandAction?.Invoke(parameter);
        }

        public Command(Action<object> action)
        {
            commandAction = action;
            IsExecutable = true;
        }
    }
}