C#使用Task在Winform建立控件上的提示等待窗口，实现局部等待加载，不影响主线程

//Loding2的类  public partial class Loading2 : UserControl, IDisposable//继承IDisposable     {         Timer timer1 = new Timer();         public Loading2(Control contorl)         {             InitializeComponent();             this.Parent = contorl;             this.Parent.Enabled = false;             this.Visible = false;//默认不显示
timer1=new System.Windows.Forms.Timer(this.components);
timer1.Interval=30000;
timer1.Tick+=new System.EventHandler(this.timer1_Tick);

        }         public void Close()         {             //自写Close方法释放资源             this.Dispose();         }
　　　　//开始运行计时以及显示         public void Start()         {             this.SendToBack();             this.Visible = true;//显示             timer1.Enabled = true;//开始计时         }         private void Loading2_Layout(object sender, LayoutEventArgs e)         {             ReLocation();//绘制位置到父级控件中间         }         private void ReLocation()         {             int x = (int)(0.5 * (Parent.Width - this.Width));             int y = (int)(0.5 * (Parent.Height - this.Height));             this.Location = new System.Drawing.Point(x, y);         }         private void timer1_Tick(object sender, EventArgs e)         {             LogHelper.Instance.Error("加载超时！");
  timer1.Stop();//手动停止，不然就算用户控件Dispose了，timer也不会释放和停止             Close();//超时关闭         }         /// <summary>         /// 使用new关键字覆盖原有System.Windows.Forms的Dispose         /// </summary>         private new void Dispose()         {             if (this.InvokeRequired)//在线程中调用，使用Invoke执行是否该用户控件代码             {                 this.Invoke(new Action(() =>                 {                     if (this.Parent != null)                     {                         this.Parent.Enabled = true;//启用父控件                     }                     Dispose(true);timer1.Dispose();//timer1是非托管资源需手动结束回收，避免任务过多导致内存问题程序奔溃                 }));             }             else             {                 if (this.Parent != null)                 {                     this.Parent.Enabled = true;                 }                 Dispose(true);timer1.Dispose();             }         }     } 

 Task<Loading2> task = null;         CancellationTokenSource cancelTokenSource = null;          private void LoadList()         {             //当上一个任务还在执行时候，最新任务到来。则取消上个任务             if (task != null)             {                 cancelTokenSource.Cancel();                 task = null;             }             cancelTokenSource = new CancellationTokenSource();             Loading2 w = new Loading2(uiGroupBox1); //这里设置了加载的Loading父级是uigroupbox             w.Start();             task = Task.Factory.StartNew(() =>             {                 LoadListData();//处理数据，里面对控件的操作需异步处理                 return w;             }, cancelTokenSource.Token);             //ContinueWith添加延续任务             task.ContinueWith(task =>             {                 task.Result.Close();//无论异常/取消/完成 都执行关闭                 if (task.IsCanceled)                 {                     //取消后执行的代码                 }                 if (task.IsCompleted)                 {                     //完成后执行的代码                 }                 if (task.IsFaulted)                 {                     //报错执行的代码                 }             },TaskContinuationOptions.AttachedToParent);//,TaskContinuationOptions标明后续任务创建方式或者和task的关系。AttachedToParent表示当前延续任务为task的子任务         }