WPF_Practice/PacticeSolution/MVVMButtonControl/Model/RelayCommand.cs

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

namespace MVVMButtonControl.Model
{
    internal class RelayCommand<T> : ICommand
    {
        private Action<T> _execute;
        private Predicate<T> _canExecute;

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

        public RelayCommand(Action<T> execute, Predicate<T> canExecute = null)
        {
            _execute = execute;
            _canExecute = canExecute;
        }

        public bool CanExecute(object? parameter)
        {
            return _canExecute?.Invoke((T)parameter) ?? true;
        }

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