參考了https://www.cnblogs.com/ZXdeveloper/p/8391864.html，自己隨便實現了一個，記錄下，比較醜

<Window x:Class="UserGuide.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:UserGuide"
        mc:Ignorable="d" 
        Title="MainWindow" Height="450" Width="800">
    <Grid>
        <Button Content="Button" HorizontalAlignment="Left" Margin="35,44,0,0" VerticalAlignment
 
="Top" Width="75" Click="Button_Click"/>
        <Button x:Name="o1" Content="Button" HorizontalAlignment="Left" Margin="274,340,0,0" VerticalAlignment="Top" Width="75"/>
        <TextBox  x:Name="o2" HorizontalAlignment="Left" Height="23" Margin="387,154,0,0" TextWrapping="Wrap" Text="TextBox"
 
 VerticalAlignment="Top" Width="120"/>
        <Label  x:Name="o3" Content="Label" HorizontalAlignment="Left" Margin="301,63,0,0" VerticalAlignment="Top"/>

        <Canvas x:Name="can" Background="#33121212"   Visibility="Collapsed" />
    </Grid>
</Window>

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
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 UserGuide
{
    /// <summary>
    /// MainWindow.xaml 的互動邏輯
    /// </summary>
    public partial class MainWindow : Window
    {

        List<GuideModel> _elList;
        int _currentIndex = 0;
        PathGeometry borGeometry = new PathGeometry();

        public MainWindow()
        {
            InitializeComponent();
            _elList = new List<GuideModel>()
            {
                new GuideModel(){ EL=o1,FBtnDesc="下一步",FDesc="這是Button"},
                new GuideModel(){ EL=o2,FBtnDesc="下一步",FDesc="這是Textbox"},
                new GuideModel(){ EL=o3,FBtnDesc="關閉",FDesc="這是label"}
            };
            
        }

        private void Button_Click(object sender, RoutedEventArgs e)
        {
            _currentIndex = 0;
            can.Visibility = Visibility.Visible;
            StartGuide();
        }


        private void CreateGuide(GuideModel el)
        {


            can.Visibility = Visibility.Visible;
            can.Children.Clear();
            Point point = el.EL.TransformToAncestor(Window.GetWindow(el.EL)).Transform(new Point(0, 0));//獲取控制元件座標點

            //設定canvas的clip
            RectangleGeometry rg = new RectangleGeometry();
            rg.Rect = new Rect(0, 0, this.ActualWidth, this.ActualHeight);
            borGeometry = Geometry.Combine(borGeometry, rg, GeometryCombineMode.Union, null);
            can.Clip = borGeometry;

            RectangleGeometry rg1 = new RectangleGeometry();
            rg1.Rect = new Rect(point.X - 5, point.Y - 5, el.EL.ActualWidth + 10, el.EL.ActualHeight + 10);
            borGeometry = Geometry.Combine(borGeometry, rg1, GeometryCombineMode.Exclude, null);

            can.Clip = borGeometry;

            UC uc = new UC();
            uc.SetLbl(el.FDesc);//設定引導描述
            uc.SetBtn(el.FBtnDesc);//設定按鈕描述
            uc.NextFlag += StartGuide;//按鈕委託
            //設定引導控制元件位置
            uc.SetValue(LeftProperty, point.X + el.EL.ActualWidth);
            uc.SetValue(TopProperty, point.Y + el.EL.ActualHeight);
            can.Children.Add(uc);

            _currentIndex++;
        }

        private void StartGuide()
        {
            if (_currentIndex >= _elList.Count)
            {
                can.Visibility = Visibility.Collapsed;
                return;
            }

            CreateGuide(_elList[_currentIndex]);
        }
    }

    public class GuideModel
    {
        public FrameworkElement EL { get; set; }
        public string FDesc { get; set; }
        public string FBtnDesc { get; set; }
    }

}

新增一個引導控制元件

<UserControl x:Class="UserGuide.UC"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
             xmlns:local="clr-namespace:UserGuide"
             mc:Ignorable="d" 
              Height="200"  Width="300">
    <Grid  Background="Red">
        <Label x:Name="lbl" Content="Label" HorizontalAlignment="Left" Margin="65,61,0,0" VerticalAlignment="Top"/>
        <Button x:Name="btn" Content="Button" HorizontalAlignment="Left" Margin="172,128,0,0" VerticalAlignment="Top" Width="75" Click="Button_Click" />

    </Grid>
</UserControl>

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
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 UserGuide
{
    /// <summary>
    /// UC.xaml 的互動邏輯
    /// </summary>
    public partial class UC : UserControl
    {

        public delegate void NextFlagHandle();
        public NextFlagHandle NextFlag;

        public UC()
        {
            InitializeComponent();
        }

        private void Button_Click(object sender, RoutedEventArgs e)
        {
            NextFlag();
        }

        public void SetLbl(string lblValue)
        {
            lbl.Content = lblValue;
        }
        public void SetBtn(string btnValue)
        {
            btn.Content = btnValue;
        }
    }
}

自己寫著玩玩的，用到專案中肯定需要美化的，基本功能實現了。