using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Linq;
using System.Runtime.CompilerServices;
using System.Text;
using System.Threading.Tasks;

namespace MVVMDemo
{
    public class BaseViewModel : INotifyPropertyChanged
    {
        public event PropertyChangedEventHandler? PropertyChanged;

        /// <summary>
        /// 更新方式，其实只要下面的就行，在这边封装一层，更方便
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="properValue"></param>
        /// <param name="newValue"></param>
        /// <param name="properName"></param>
        protected void UpdateProperty<T>(ref T properValue, T newValue, [CallerMemberName] string properName = "")
        {
            //对比新旧值，如果相等就不更新
            if (object.Equals(properValue, newValue))
                return;
            properValue = newValue;
            NotifyPropertyChanged(properName);
        }

        /// <summary>
        /// 最基础的方式
        /// </summary>
        /// <param name="propertyName"></param>
        //public void NotifyPropertyChanged([CallerMemberName] string propertyName = null)//参数加上此标记就可以不用传递参数了
        public void NotifyPropertyChanged(string propertyName)
        {
            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
        }
    }
}