WPF 子类访问主类（父类）MainWindow的属性和方法

工程集如下：

<Window x:Class="SubClassCallMainClass.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:SubClassCallMainClass"
        mc:Ignorable="d"
        Title="MainWindow" Height="450" Width="800">
    <Grid>
        <Grid >
            <RichTextBox   VerticalScrollBarVisibility="Auto" HorizontalScrollBarVisibility="Auto" TextChanged="LogTextChanged" Margin="0,0,0,79" >
                <FlowDocument>
                    <Paragraph x:Name="myParagraph" />
                </FlowDocument>
            </RichTextBox>
            <Button x:Name="myButton" Content="开始" Click="BtnClickWork" HorizontalAlignment="Left" Margin="400,380,0,0" VerticalAlignment="Top"/>
            <Button Content="显示" Click="BtnClickDis" HorizontalAlignment="Left" Margin="478,380,0,0" VerticalAlignment="Top"/>
        </Grid>
    </Grid>
</Window>

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;

namespace SubClassCallMainClass
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        public int num = 0;
        public MainWindow()
        {
            InitializeComponent();
            myWriteLog(Brushes.Black, "主类调用自己的方法");

        }

        #region 打印日志方法

        public void myWriteLog(SolidColorBrush color, string str)
        {
            myParagraph.Dispatcher.Invoke(new Action(() =>
            {
                Run run = new Run() { Text = str, Foreground = color };
                myParagraph.Inlines.Add(run);
                myParagraph.Inlines.Add(new LineBreak());//换行（如果用
也能换行，但是要把内容拷贝到Word里面
换行符不能识别，推荐使用LineBreak()来换行）
            }));
        }

        #endregion
        private void LogTextChanged(object sender, TextChangedEventArgs e)
        {
            RichTextBox richTextBox = sender as RichTextBox;
            richTextBox.ScrollToEnd();
        }

        private void BtnClickWork(object sender, RoutedEventArgs e)
        {
            Work myWork = new Work();//实例化子类Work
            myWork.DoWork(this);//this 就是MainWindow类的实例,通过参数传递给子类Work,这样Work类就可以访问MainWindow的属性和方法了
        }

        private void BtnClickDis(object sender, RoutedEventArgs e)
        {
            myWriteLog(Brushes.Black, $"主类num{num}");
        }
    }
}

using System;
using System.Collections.Generic;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using System.Windows.Media;

namespace SubClassCallMainClass
{
    public class Work
    {
        public void DoWork(MainWindow mainWindow)
        {
            var order = Task.Run(() =>
            {
                for (; ; )
                {
                    mainWindow.num++;//更改MainWindow.xaml.cs主类的属性
                    Thread.Sleep(1000);
                    mainWindow.myWriteLog(Brushes.Red, $"子类调用主类的方法,并且更改主类属性num:{mainWindow.num}");//访问MainWindow.xaml.cs主类的方法
                }
            });
        }

    }
}

 效果如下：

 把MainWindow.xaml.cs中的按键事件处理内容放到Work类中去处理，当工程比较大的时候，这样便于工程管理,源码下载地址：https://github.com/lizhiqiang0204/SubClassCallMainClass