VanDalkvist
3/19/2015 - 7:33 AM

Commands structure

Commands structure

using System;
using System.Windows.Input;
using System.Windows.Markup;

namespace Commands
{
    public class RelayCommand : MarkupExtension, ICommand
    {
        private readonly Func<object, bool> _canExecute;
        private readonly Action<object> _execute;

        public RelayCommand(Action<object> execute, Func<object, bool> canExecute = null)
        {
            _execute = execute;
            _canExecute = canExecute;
        }

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

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

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

        public override object ProvideValue(IServiceProvider serviceProvider)
        {
            return this;
        }
    }
}
using System;
using System.Collections.Generic;
using System.Linq;
using System.Windows.Input;
using System.Windows.Markup;

namespace Commands
{
    public class DelegateCommand : MarkupExtension, ICommand
    {
        public IEnumerable<Command> Commands { get; set; }

        public DelegateCommand()
        {
            Commands = new Command[] { };
        }

        public DelegateCommand(IEnumerable<Command> commands)
        {
            Commands = commands;
        }

        public bool CanExecute(object parameter)
        {
            return Commands != null && Commands.Any();
        }

        public void Execute(object parameter)
        {
            if (CanExecute(parameter))
                foreach (var command in Commands)
                {
                    var param = command.UseParentParameter ? parameter : command.Parameter;
                    var action = command.Action;

                    if (action.CanExecute(param)) action.Execute(param);
                }
        }

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

        public override object ProvideValue(IServiceProvider serviceProvider)
        {
            return this;
        }
    }
}
using System;
using System.Windows.Input;
using System.Windows.Markup;

namespace Commands
{
    public class Command : MarkupExtension
    {
        public Command()
        {
            UseParentParameter = false;
        }

        public ICommand Action { get; set; }

        public object Parameter { get; set; }

        public bool UseParentParameter { get; set; }

        public static Command CreateCommand(Action<object> executeAction, object parameter = null, Func<object, bool> canExecuteAction = null)
        {
            Func<object, bool> canExecute = o => true;
            if (canExecuteAction != null) canExecute = canExecuteAction.Invoke;

            return new Command
            {
                Action = new RelayCommand(executeAction.Invoke, canExecute),
                Parameter = parameter
            };
        }

        public override object ProvideValue(IServiceProvider serviceProvider)
        {
            return this;
        }
    }
}