标签：protect 一个 exception esc ogre form handler 异常 ati
在设计应用程序过程中，有时候加载对象需时较长，我们可以显示一个Loading等待页面，对用户来说就比较友好了。
这个还是涉及到多线程，下面是步骤。
一、创建好Loading窗体：
一个Panel用于显示转圈动画（仿Win10的Loading），一个Loading文本标签。动画的代码来自网络。
public partial class Fm20Loading : Form { public Fm20Loading() { InitializeComponent(); //LblMessage.Text = MultiLang.Surface(null, "OnLoading", "目标对象正在加载中, 请您稍等..."); SetStyle( ControlStyles.AllPaintingInWmPaint | ControlStyles.UserPaint | ControlStyles.OptimizedDoubleBuffer, true); //初始化绘图timer _tmrGraphics = new UITimer { Interval = 1 }; //Invalidate()强制重绘,绘图操作在OnPaint中实现 _tmrGraphics.Tick += (sender, e) => PnlImage.Invalidate(false); _dotSize = PnlImage.Width / 10f; //初始化"点" _dots = new LoadingDot[5]; Color = Color.CadetBlue; } /// <summary> /// 构造器 /// </summary> /// <param name="message"></param> public Fm20Loading(string message) { InitializeComponent(); //双缓冲，禁擦背景 SetStyle( ControlStyles.AllPaintingInWmPaint | ControlStyles.UserPaint | ControlStyles.OptimizedDoubleBuffer, true); //初始化绘图timer _tmrGraphics = new UITimer { Interval = 1 }; //Invalidate()强制重绘,绘图操作在OnPaint中实现 _tmrGraphics.Tick += (sender, e) => PnlImage.Invalidate(false); _dotSize = PnlImage.Width / 10f; //初始化"点" _dots = new LoadingDot[5]; Color = Color.CadetBlue; Message = message; } private void Fm20Loading_Load(object sender, EventArgs e) { LblMessage.ForeColor = Color; if (Owner != null) { StartPosition = FormStartPosition.Manual; Location = new Point(Owner.Left, Owner.Top); Width = Owner.Width; Height = Owner.Height; } else { var screenRect = Screen.PrimaryScreen.WorkingArea; Location = new Point((screenRect.Width - Width) / 2, (screenRect.Height - Height) / 2); } Start(); } private void Fm20Loading_Shown(object sender, EventArgs e) { if (_workAction != null) { _workThread = new Thread(ExecWorkAction) { IsBackground = true }; _workThread.Start(); } } #region 属性 [Description("消息")] public string Message { get { return LblMessage.Text; } set { LblMessage.Text = value; } } [Browsable(false), Description("圆心")] public PointF CircleCenter => new PointF(PnlImage.Width / 2f, PnlImage.Height / 2f); [Browsable(false), Description("半径")] public float CircleRadius => PnlImage.Width / 2f - _dotSize; [Browsable(true), Category("Appearance"), Description("设置\"点\"的前景色")] public Color Color { get; set; } #endregion 属性 #region 字段 [Description("工作是否完成")] public bool IsWorkCompleted; [Description("工作动作")] private ParameterizedThreadStart _workAction; [Description("工作动作参数")] private object _workActionArg; [Description("工作线程")] private Thread _workThread; [Description("工作异常")] public Exception WorkException { get; private set; } [Description("点数组")] private readonly LoadingDot[] _dots; [Description("UITimer")] private readonly UITimer _tmrGraphics; [Description("ThreadingTimer")] private ThreadingTimer _tmrAction; [Description("点大小")] private float _dotSize; [Description("是否活动")] private bool _isActived; [Description("是否绘制：用于状态重置时挂起与恢复绘图")] private bool _isDrawing = true; [Description("Timer计数：用于延迟启动每个点 ")] private int _timerCount; #endregion 字段 #region 常量 [Description("动作间隔(Timer)")] private const int ActionInterval = 30; [Description("计数基数：用于计算每个点启动延迟：index * timerCountRadix")] private const int TimerCountRadix = 45; #endregion 常量 #region 方法 /// <summary> /// 设置工作动作 /// </summary> /// <param name="workAction"></param> /// <param name="arg"></param> public void SetWorkAction(ParameterizedThreadStart workAction, object arg) { _workAction = workAction; _workActionArg = arg; } /// <summary> /// 执行工作动作 /// </summary> private void ExecWorkAction() { try { var workTask = new Task(arg => { _workAction(arg); }, _workActionArg); workTask.Start(); Task.WaitAll(workTask); } catch (Exception exception) { WorkException = exception; } finally { IsWorkCompleted = true; } } /// <summary> /// 检查是否重置 /// </summary> /// <returns></returns> private bool CheckToReset() { return _dots.Count(d => d.Opacity > 0) == 0; } /// <summary> /// 初始化点元素 /// </summary> private void CreateLoadingDots() { for (var i = 0; i < _dots.Length; ++i) _dots[i] = new LoadingDot(CircleCenter, CircleRadius); } /// <summary> /// 开始 /// </summary> public void Start() { CreateLoadingDots(); _timerCount = 0; foreach (var dot in _dots) { dot.Reset(); } _tmrGraphics.Start(); //初始化动作timer _tmrAction = new ThreadingTimer( state => { //动画动作 for (var i = 0; i < _dots.Length; i++) { if (_timerCount++ > i * TimerCountRadix) { _dots[i].LoadingDotAction(); } } //是否重置 if (CheckToReset()) { //重置前暂停绘图 _isDrawing = false; _timerCount = 0; foreach (var dot in _dots) { dot.Reset(); } //恢复绘图 _isDrawing = true; } _tmrAction.Change(ActionInterval, Timeout.Infinite); }, null, ActionInterval, Timeout.Infinite); _isActived = true; } /// <summary> /// 停止 /// </summary> public void Stop() { _tmrGraphics.Stop(); _tmrAction.Dispose(); _isActived = false; } #endregion 方法 #region 重写 protected override void OnPaint(PaintEventArgs e) { if (IsWorkCompleted) { Stop(); Close(); } } private void PnlImage_Paint(object sender, PaintEventArgs e) { if (_isActived && _isDrawing) { //抗锯齿 e.Graphics.SmoothingMode = SmoothingMode.HighQuality; using (var bitmap = new Bitmap(200, 200)) { //缓冲绘制 using (var bufferGraphics = Graphics.FromImage(bitmap)) { //抗锯齿 bufferGraphics.SmoothingMode = SmoothingMode.HighQuality; foreach (var dot in _dots) { var rectangleF = new RectangleF( new PointF(dot.Location.X - _dotSize / 2, dot.Location.Y - _dotSize / 2), new SizeF(_dotSize, _dotSize)); bufferGraphics.FillEllipse(new SolidBrush(Color.FromArgb(dot.Opacity, Color)), rectangleF); } } //贴图 e.Graphics.DrawImage(bitmap, new PointF(0, 0)); } //bmp disposed } base.OnPaint(e); } private void PnlImage_Resize(object sender, EventArgs e) { PnlImage.Height = PnlImage.Width; _dotSize = PnlImage.Width / 12f; OnResize(e); } #endregion 重写 private void LblMessage_DoubleClick(object sender, EventArgs e) { this.Close(); } }
internal sealed class LoadingDot { #region 字段/属性 [Description("圆心")] private readonly PointF _circleCenter; [Description("半径")] private readonly float _circleRadius; /// <summary> /// 当前帧绘图坐标，在每次DoAction()时重新计算 /// </summary> public PointF Location; [Description("点相对于圆心的角度，用于计算点的绘图坐标")] private int _angle; [Description("透明度")] private int _opacity; [Description("动画进度")] private int _progress; [Description("速度")] private int _speed; [Description("透明度")] public int Opacity => _opacity < MinOpacity ? MinOpacity : (_opacity > MaxOpacity ? MaxOpacity : _opacity); #endregion #region 常量 [Description("最小速度")] private const int MinSpeed = 2; [Description("最大速度")] private const int MaxSpeed = 11; [Description("出现区的相对角度")] private const int AppearAngle = 90; [Description("减速区的相对角度")] private const int SlowAngle = 225; [Description("加速区的相对角度")] private const int QuickAngle = 315; [Description("最小角度")] private const int MinAngle = 0; [Description("最大角度")] private const int MaxAngle = 360; [Description("淡出速度")] private const int AlphaSub = 25; [Description("最小透明度")] private const int MinOpacity = 0; [Description("最大透明度")] private const int MaxOpacity = 255; #endregion 常量 #region 构造器 public LoadingDot(PointF circleCenter, float circleRadius) { Reset(); _circleCenter = circleCenter; _circleRadius = circleRadius; } #endregion 构造器 #region 方法 /// <summary> /// 重新计算当前帧绘图坐标 /// </summary> private void ReCalcLocation() { Location = GetDotLocationByAngle(_circleCenter, _circleRadius, _angle); } /// <summary> /// 点动作 /// </summary> public void LoadingDotAction() { switch (_progress) { case 0: { _opacity = MaxOpacity; AddSpeed(); if (_angle + _speed >= SlowAngle && _angle + _speed < QuickAngle) { _progress = 1; _angle = SlowAngle - _speed; } } break; case 1: { SubSpeed(); if (_angle + _speed >= QuickAngle || _angle + _speed < SlowAngle) { _progress = 2; _angle = QuickAngle - _speed; } } break; case 2: { AddSpeed(); if (_angle + _speed >= SlowAngle && _angle + _speed < QuickAngle) { _progress = 3; _angle = SlowAngle - _speed; } } break; case 3: { SubSpeed(); if (_angle + _speed >= QuickAngle && _angle + _speed < MaxAngle) { _progress = 4; _angle = QuickAngle - _speed; } } break; case 4: { SubSpeed(); if (_angle + _speed >= MinAngle && _angle + _speed < AppearAngle) { _progress = 5; _angle = MinAngle; } } break; case 5: { AddSpeed(); FadeOut(); } break; } //移动 _angle = _angle >= (MaxAngle - _speed) ? MinAngle : _angle + _speed; //重新计算坐标 ReCalcLocation(); } /// <summary> /// 淡出 /// </summary> private void FadeOut() { if ((_opacity -= AlphaSub) <= 0) _angle = AppearAngle; } /// <summary> /// 重置状态 /// </summary> public void Reset() { _angle = AppearAngle; _speed = MinSpeed; _progress = 0; _opacity = 1; } /// <summary> /// 加速 /// </summary> private void AddSpeed() { if (++_speed >= MaxSpeed) _speed = MaxSpeed; } /// <summary> /// 减速 /// </summary> private void SubSpeed() { if (--_speed <= MinSpeed) _speed = MinSpeed; } #endregion 方法 /// <summary> /// 根据半径、角度求圆上坐标 /// </summary> /// <param name="center">圆心</param> /// <param name="radius">半径</param> /// <param name="angle">角度</param> /// <returns>坐标</returns> public static PointF GetDotLocationByAngle(PointF center, float radius, int angle) { var x = (float)(center.X + radius * Math.Cos(angle * Math.PI / 180)); var y = (float)(center.Y + radius * Math.Sin(angle * Math.PI / 180)); return new PointF(x, y); } }
二、窗体和动画有了，怎么使用呢？
private void ShowLoadingForm() { if (Debugger.IsAttached) { return; } Fm20Loading fm20Loading = new Fm20Loading { Name = "Fm20Loading" + DateTime.Now.Ticks }; Thread.Sleep(100); fm20Loading.ShowDialog(); return ; } private void CloseLoadingForm() { if (Debugger.IsAttached) return; for (int i = (Application.OpenForms.Count-1); i >=0; i--) { Form tForm = Application.OpenForms[i]; string fmName = tForm.GetType().Name; if (OString.Left(fmName,11) == "Fm20Loading") { tForm.Close(); } } }
三、调用创建和关闭代码的代码（有点绕了）
try
{
Form child = ActiveChildForm(dllFormNameWithNameSpace);
if (child != null) return child;
Action handler = new Action(ShowLoadingForm);
handler.BeginInvoke(null, null); //在另外一个线程打开，否则会阻塞
Form form = OpenPluginFormInMainDomain(dllFileSimpleName, dllFormNameWithNameSpace, initParam);
if (form != null && form is Form)
{
child = form as Form;
((Fm11Base)child).RightsList = rightsList.ToLower();
((Fm11Base)child).OnLoadParams = onLoadParams;
child.Text = tagTitle;
child.MdiParent = (Form)this;
child.FormClosed += Child_FormClosed;
child.Show();
child.WindowState = FormWindowState.Maximized;
this.ActivateMdiChild(child);
if (child.HasChildren)
{
child.Controls[0].Focus();
}
CloseLoadingForm();
return child;
}
else
{
CloseLoadingForm();
return null;
throw new Exception("未找到窗体文件或加载了未知的窗体类型!");
}
}
catch (Exception ex)
{
CloseLoadingForm();
MyMsg.Information("窗体实例化出错,请重试.", ex.Message);
return null;
}
这部分可以改成你喜欢的使用环境。
如此，一个友好的加载等待页面就完成了。它和耗时后台任务提示窗口两种界面结合，可以解决大部分的友好提示界面需求。
标签：protect 一个 exception esc ogre form handler 异常 ati
原文地址：https://www.cnblogs.com/imes/p/9779331.html
