用微软自带的 IOC 需要安装

using Microsoft.Extensions.DependencyInjection;
using System.Configuration;
using System.Data;
using System.Windows;

namespace WpfApp3
{
    /// <summary>
    /// Interaction logic for App.xaml
    /// </summary>
    public partial class App : Application
    {
        /// <summary>
        /// 定义服务通道
        /// </summary>
        public IServiceProvider Services { get; }

        /// <summary>
        /// 设置当前正在使用的App实例
        /// 因为父类Application有这个属性，子类要隐藏父类，需要用new修饰
        /// </summary>
        public new static App Current=> (App)Application.Current;
        public App()
        {
            IServiceCollection sc= new ServiceCollection();
            sc.AddSingleton(typeof(ILog), typeof(Log));
            sc.AddTransient(typeof(MainViewModel));
            this.Services=sc.BuildServiceProvider();
        }
    }

}

案例