using System;
using System.Collections.Generic;
using System.Text;
using System.Drawing;
using System.ComponentModel;
using System.Windows.Forms;
namespace Line
{
public class LineControl : Control
{
private LineType m_lineType = LineType.Horizontal;
private Color m_lineColor = Color.Blue;
private Color m_shadowColor = Color.Gray;
private int m_lineWidth = 2;
private Size m_shadowOffset = new Size(1, 1);
public LineControl()
{
this.SetStyle(ControlStyles.ResizeRedraw | ControlStyles.UserPaint | ControlStyles.SupportsTransparentBackColor, true);
this.SetStyle(ControlStyles.UserMouse |
ControlStyles.Selectable |
ControlStyles.StandardClick |
ControlStyles.StandardDoubleClick, false);
}
[Category("線")]
[Description("陰影的偏移量")]
[DefaultValue(typeof(Size), "1,1")]
public Size ShadowOffset
{
get { return m_shadowOffset; }
set
{
m_shadowOffset = value;
this.SetSize();
this.Invalidate();
}
}
[Category("線")]
[Description("寬度")]
[DefaultValue(2)]
public int LineWidth
{
get { return m_lineWidth; }
set
{
if (value < 1) value = 1;
m_lineWidth = value;
this.SetSize();
this.Invalidate();
}
}
[Category("線")]
[Description("類型")]
[DefaultValue(typeof(LineType), "Horizontal")]
public LineType LineType
{
get { return m_lineType; }
set
{
if (m_lineType != value)
{
int linelen = 0;
if (m_lineType == LineType.Horizontal)
{
linelen = this.Width;
}
else
{
linelen = this.Height;
}
m_lineType = value;
if (value == LineType.Horizontal)
{
this.Width = linelen;
}
else
{
this.Height = linelen;
}
this.SetSize();
this.Invalidate();
}
}
}
[Category("線")]
[Description("顏色")]
[DefaultValue(typeof(Color), "Blue")]
public Color LineColor
{
get { return m_lineColor; }
set
{
m_lineColor = value;
this.Invalidate();
}
}
[Category("線")]
[Description("陰影的顏色")]
[DefaultValue(typeof(Color), "Gray")]
public Color ShadowColor
{
get { return m_shadowColor; }
set
{
m_shadowColor = value;
this.Invalidate();
}
}
protected override void OnPaint(PaintEventArgs e)
{
Pen p1 = new Pen(this.LineColor, this.LineWidth);
Pen p2 = new Pen(this.ShadowColor, this.LineWidth);
if (this.LineType == LineType.Horizontal)
{
e.Graphics.DrawLine(p2, new Point(ShadowOffset.Width, ShadowOffset.Height), new Point(this.Right, ShadowOffset.Height));
e.Graphics.DrawLine(p1, Point.Empty, new Point(this.Right - ShadowOffset.Width, 0));
}
else
{
e.Graphics.DrawLine(p2, new Point(ShadowOffset.Width, ShadowOffset.Height), new Point(ShadowOffset.Width, this.Bottom));
e.Graphics.DrawLine(p1, Point.Empty, new Point(0, this.Bottom - ShadowOffset.Height));
}
p1.Dispose();
p2.Dispose();
}
protected override void OnSizeChanged(EventArgs e)
{
base.OnSizeChanged(e);
SetSize();
}
private void SetSize()
{
if (this.LineType == LineType.Horizontal)
{
this.Height = LineWidth + ShadowOffset.Height;
}
else
{
this.Width = LineWidth + ShadowOffset.Width;
}
}
}
/// <summary>
/// 線的類型
/// </summary>
public enum LineType
{
/// <summary>
/// 橫線
/// </summary>
Horizontal,
/// <summary>
/// 豎線
/// </summary>
Vertical
}
}
摘自 Allen Chen 的專欄
