C#圆形Button——RoundButton

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace YcPackageTool.Widgets
{
class RoundButton : Button
{
private int radius;//半径

//圆形按钮的半径属性
[CategoryAttribute("布局"), BrowsableAttribute(true), ReadOnlyAttribute(false)]
public int Radius
{
set
{
radius = value;
this.Height = this.Width = Radius;
}
get
{
return radius;
}
}

private Image imageEnter;
[CategoryAttribute("外观"), BrowsableAttribute(true), ReadOnlyAttribute(false)]
public Image ImageEnter
{
set
{
imageEnter = value;
}
get
{
return imageEnter;
}
}

private Image imageNormal;
[CategoryAttribute("外观"), BrowsableAttribute(true), ReadOnlyAttribute(false)]
public Image ImageNormal
{
set
{
imageNormal = value;
BackgroundImage = imageNormal;
}
get
{
return imageNormal;
}
}

//以下代码用于在VS中隐藏BackgroundImage属性，使得只能通过Diameter设置Height和Width
[BrowsableAttribute(false)]
public new Image BackgroundImage
{
get
{
return base.BackgroundImage;
}
set
{
base.BackgroundImage = value;

}
}

//以下代码用于在VS中隐藏Size属性，使得只能通过Diameter设置Height和Width
[BrowsableAttribute(false)]
public new Size Size
{
get
{
return base.Size;
}
set
{
base.Size = value;

}
}

public RoundButton()
{
Radius = 64;
this.Height = this.Width = Radius;
this.FlatStyle = FlatStyle.Flat;
this.FlatAppearance.BorderSize = 0;
this.BackgroundImage = imageEnter;
this.BackgroundImageLayout = ImageLayout.Stretch;
}

//重写OnPaint
protected override void OnPaint(System.Windows.Forms.PaintEventArgs e)
{
base.OnPaint(e);
System.Drawing.Drawing2D.GraphicsPath path = new System.Drawing.Drawing2D.GraphicsPath();
path.AddEllipse(0, 0, Radius, Radius);
this.Region = new Region(path);
}

//重写OnMouseEnter
//protected override void OnMouseEnter(EventArgs e)
//{
//    Graphics g = this.CreateGraphics();
//    g.DrawEllipse(new Pen(Color.Blue), 0, 0, this.Width, this.Height);
//    g.Dispose();
//}

//重写OnSizeChanged
protected override void OnSizeChanged(EventArgs e)
{
base.OnSizeChanged(e);
if (Height != Radius)
{
Radius = Width = Height;
}
else if (Width != Radius)
{
Radius = Height = Width;
}

}

//重写OnMouseEnter
protected override void OnMouseEnter(EventArgs e)
{
base.OnMouseEnter(e);
BackgroundImage = ImageEnter;
}

//重写OnMouseLeave
protected override void OnMouseLeave(EventArgs e)
{
base.OnMouseLeave(e);
BackgroundImage = ImageNormal;
}
}
}