C# 浮动窗口 屏幕右下角显示但不获得焦点 工程上右键添加系统引用System.Drawing

C# 浮动窗口 屏幕右下角显示但不获得焦点 工程上右键添加系统引用System.Drawing

//注意在工程上添加系统引用System.Drawing 否则System点不出Drawing来。

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using DevComponents.DotNetBar;

namespace TaskBarFloatWnd
{
    public partial class Form1 : Office2007Form
    {
        public Form1()
        {
            InitializeComponent();
           
        }

      

        private void button1_Click(object sender, EventArgs e)
        {

            TaskBarWnd taskWnd = new TaskBarWnd();
            System.Drawing.Rectangle r = System.Windows.Forms.Screen.GetWorkingArea(taskWnd);
            taskWnd.Location = new System.Drawing.Point(r.Right - taskWnd.Width, r.Bottom - taskWnd.Height);
            taskWnd.Show();
        }
    }
}

using  System;
using  System.Collections.Generic;
using  System.ComponentModel;
using  System.Data;
using  System.Drawing;
using  System.Text;
using  System.Windows.Forms;
using  DevComponents.DotNetBar;

namespace  TaskBarFloatWnd
{
    public partial class TaskBarWnd : Office2007Form
    {
        public TaskBarWnd()
        {
            InitializeComponent();
            actform = GetActiveWindow();
        }
        private bool isFristShow = true;//标识是否是首次加载
        [System.Runtime.InteropServices.DllImport("user32.dll")]
        public static extern IntPtr GetActiveWindow();//获得当前活动窗体
        [System.Runtime.InteropServices.DllImport("user32.dll")]
        public static extern IntPtr SetActiveWindow(IntPtr hwnd);//设置活动窗体

        private IntPtr actform = IntPtr.Zero;//保存自己得到焦点前拥有活动窗体的柄
        private void TaskBarWnd_Load(object sender, EventArgs e)
        {
            textBox1.Text = DateTime.Now + "——";
            textBox1.Text = textBox1.Text + "目前正对网元1进行做单操作，10分钟内请大家避让";

        }
        protected override void OnActivated(EventArgs e)
        {
            base.OnActivated(e);
            if (isFristShow == true)
            {
                SetActiveWindow(actform);
                isFristShow = false;
            }
        }

       

        private void TaskBarWnd_FormClosing(object sender, FormClosingEventArgs e)
        {
            
        }
    }
}