C#使用Stateless和箭头控件实现状态机的控制及显示
之前开发一个小工具，内部实现一个状态机，并显示状态机当前状态及状态间的转移过程。我使用了Stateless开源类库及一个开源自定义箭头控件。自定义箭头控件是HZHControls其中一个控件，我单独把它从源码中独立出来。主要对代码做了以下改动：
- 添加、删除、替换了一部分注释。
- 更改了一些内部事件触发逻辑，时间长了忘了具体改了什么，但不会影响主体功能。
- 在 protected override void OnPaint(PaintEventArgs e) 中内联了外部依赖的 public static void SetGDIHigh(Graphics g) 函数，我在原作者博客的评论下有说明。
以上涉及到的相关项目的链接如下
- Stateless开源类库：https://github.com/dotnet-state-machine/stateless
- HZHControls控件库：https://gitee.com/kwwwvagaa/net_winform_custom_control
- Stateless使用方法：.NET中的状态机库Stateless
- 自定义箭头控件介绍：（六十三）c#Winform自定义控件-箭头（工业）-HZHControls
自定义箭头控件的代码很有学习价值，可以在其基础上扩展出其它形状的控件。使用时新建一个用户控件然后复制代码即可，代码如下：
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.ComponentModel;
namespace ExtControls
{
public partial class Arrow : UserControl
{
private Color arrowColor = Color.DarkGray;
/// <summary>
/// 获取设置箭头颜色
/// </summary>
[Description("箭头颜色"), Category("自定义")]
public Color ArrowColor
{
get { return arrowColor; }
set
{
arrowColor = value;
Refresh();
}
}
private Color? borderColor = null;
/// <summary>
/// 获取或设置箭头边框颜色
/// </summary>
[Description("箭头边框颜色，为空则无边框"), Category("自定义")]
public Color? BorderColor
{
get { return borderColor; }
set
{
borderColor = value;
Refresh();
}
}
/// <summary>
/// 箭头方向
/// </summary>
private ArrowDirection direction = ArrowDirection.Right;
/// <summary>
/// 获取或设置箭头方向
/// </summary>
/// <value>The direction.</value>
[Description("获取或设置箭头方向"), Category("自定义")]
public ArrowDirection Direction
{
get { return direction; }
set
{
direction = value;
ResetMyPath();
Refresh();
}
}
private string text;
/// <summary>
/// 与控件关联的文本。
/// </summary>
[Bindable(true)]
[Browsable(true)]
[DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)]
[EditorBrowsable(EditorBrowsableState.Always)]
[Localizable(true)]
[Description("与控件关联的文本"), Category("自定义")]
public override string Text
{
get
{
return text;
}
set
{
text = value;
Refresh();
}
}
/// <summary>
/// 图形空间
/// </summary>
GraphicsPath myPath;
/// <summary>
/// 初始化UCArrow类的新实例。
/// </summary>
public Arrow()
{
this.SetStyle(ControlStyles.AllPaintingInWmPaint, true);
this.SetStyle(ControlStyles.DoubleBuffer, true);
this.SetStyle(ControlStyles.ResizeRedraw, true);
this.SetStyle(ControlStyles.Selectable, true);
this.SetStyle(ControlStyles.SupportsTransparentBackColor, true);
this.SetStyle(ControlStyles.UserPaint, true);
this.ForeColor = Color.White;
this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.None;
this.SizeChanged += UCArrow_NeedResetChanged;
this.Size = new Size(100, 50);
this.ForeColorChanged += UCArrow_NeedResetChanged;
this.ForeColor = Color.Black;
this.FontChanged += UCArrow_NeedResetChanged;
}
/// <summary>
/// 需要重绘控件的事件
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
void UCArrow_NeedResetChanged(object sender, EventArgs e)
{
ResetMyPath();
}
/// <summary>
/// 重置图形
/// </summary>
private void ResetMyPath()
{
Point[] ps = null;
switch (direction)
{
case ArrowDirection.Left:
ps = new Point[]
{
new Point(0,this.Height/2),
new Point(40,0),
new Point(40,this.Height/4),
new Point(this.Width-1,this.Height/4),
new Point(this.Width-1,this.Height-this.Height/4),
new Point(40,this.Height-this.Height/4),
new Point(40,this.Height),
new Point(0,this.Height/2)
};
break;
case ArrowDirection.Right:
ps = new Point[]
{
new Point(0,this.Height/4),
new Point(this.Width-40,this.Height/4),
new Point(this.Width-40,0),
new Point(this.Width-1,this.Height/2),
new Point(this.Width-40,this.Height),
new Point(this.Width-40,this.Height-this.Height/4),
new Point(0,this.Height-this.Height/4),
new Point(0,this.Height/4)
};
break;
case ArrowDirection.Top:
ps = new Point[]
{
new Point(this.Width/2,0),
new Point(this.Width,40),
new Point(this.Width-this.Width/4,40),
new Point(this.Width-this.Width/4,this.Height-1),
new Point(this.Width/4,this.Height-1),
new Point(this.Width/4,40),
new Point(0,40),
new Point(this.Width/2,0),
};
break;
case ArrowDirection.Bottom:
ps = new Point[]
{
new Point(this.Width-this.Width/4,0),
new Point(this.Width-this.Width/4,this.Height-40),
new Point(this.Width,this.Height-40),
new Point(this.Width/2,this.Height-1),
new Point(0,this.Height-40),
new Point(this.Width/4,this.Height-40),
new Point(this.Width/4,0),
new Point(this.Width-this.Width/4,0),
};
break;
case ArrowDirection.Left_Right:
ps = new Point[]
{
new Point(0,this.Height/2),
new Point(40,0),
new Point(40,this.Height/4),
new Point(this.Width-40,this.Height/4),
new Point(this.Width-40,0),
new Point(this.Width-1,this.Height/2),
new Point(this.Width-40,this.Height),
new Point(this.Width-40,this.Height-this.Height/4),
new Point(40,this.Height-this.Height/4),
new Point(40,this.Height),
new Point(0,this.Height/2),
};
break;
case ArrowDirection.Top_Bottom:
ps = new Point[]
{
new Point(this.Width/2,0),
new Point(this.Width,40),
new Point(this.Width-this.Width/4,40),
new Point(this.Width-this.Width/4,this.Height-40),
new Point(this.Width,this.Height-40),
new Point(this.Width/2,this.Height-1),
new Point(0,this.Height-40),
new Point(this.Width/4,this.Height-40),
new Point(this.Width/4,40),
new Point(0,40),
new Point(this.Width/2,0),
};
break;
}
myPath = new GraphicsPath();
myPath.AddLines(ps);
myPath.CloseAllFigures();
}
/// <summary>
/// 引发Control.Paint 事件。
/// </summary>
/// <param name="e"></param>
protected override void OnPaint(PaintEventArgs e)
{
base.OnPaint(e);
var g = e.Graphics;
// 设置GDI高质量模式抗锯齿
g.SmoothingMode = SmoothingMode.AntiAlias;
g.InterpolationMode = InterpolationMode.HighQualityBicubic;
g.CompositingQuality = CompositingQuality.HighQuality;
g.FillPath(new SolidBrush(arrowColor), myPath);
if (borderColor != null && borderColor != Color.Empty)
g.DrawPath(new Pen(new SolidBrush(borderColor.Value)), myPath);
if (!string.IsNullOrEmpty(text))
{
var size = g.MeasureString(Text, Font);
g.DrawString(Text, Font, new SolidBrush(ForeColor), new PointF((this.Width - size.Width) / 2, (this.Height - size.Height) / 2));
}
}
}
/// <summary>
/// 箭头方向的描述枚举
/// </summary>
public enum ArrowDirection
{
/// <summary>
/// 向左
/// </summary>
Left,
/// <summary>
/// 向右
/// </summary>
Right,
/// <summary>
/// 向上
/// </summary>
Top,
/// <summary>
/// 向下
/// </summary>
Bottom,
/// <summary>
/// 向左向右
/// </summary>
Left_Right,
/// <summary>
/// 向上向下
/// </summary>
Top_Bottom
}
}
