WPF INotifyPropertyChanged和ICommand使用

INotifyPropertyChanged和ICommand使用

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INotifyPropertyChanged

INotifyPropertyChanged 的作用： 通知客户端属性值已经更改。

实现接口如下

    public class BaseViewModel : INotifyPropertyChanged
    {
    
    
        public event PropertyChangedEventHandler PropertyChanged;

        public void RaisePropertyChanged([CallerMemberName] string propertyName = null)
        {
    
    
            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));

        }
    }

ICommand

ICommand实现接口如下

  public class RelayCommand<T> : ICommand
    {
    
    
        /// <summary>
        /// 命令能否执行
        /// </summary>
        readonly Func<bool> _canExecute;

        /// <summary>
        /// 命令执行的方法
        /// </summary>
        readonly Action<T> _execute;

        /// <summary>
        /// 命令的构造函数
        /// </summary>
        /// <param name="act">命令需执行的方法</param>
        /// <param name="func">命令是否可以执行的方法</param>
        public RelayCommand(Action<T> act, Func<bool> func)
        {
    
    
            _execute = act;
            _canExecute = func;
        }

        /// <summary>
        /// 事件追加、移除
        /// </summary>
        public event EventHandler CanExecuteChanged
        {
    
    
            add
            {
    
    
                if (_canExecute != null)
                {
    
    
                    CommandManager.RequerySuggested += value;
                }
            }
            remove
            {
    
    
                if (_canExecute != null)
                {
    
    
                    CommandManager.RequerySuggested -= value;
                }
            }
        }

        /// <summary>
        /// 判断命令是否可以执行
        /// </summary>
        /// <param name="parameter"></param>
        /// <returns></returns>
        public bool CanExecute(object parameter)
        {
    
    
            if (_canExecute == null)
            {
    
    
                return true;
            }
            return _canExecute();
        }

        /// <summary>
        /// 执行命令
        /// </summary>
        /// <param name="parameter"></param>
        public void Execute(object parameter)
        {
    
    
            _execute((T)parameter);
        }
    }