前提
入行已经7,8年了，一直想做一套漂亮点的自定义控件，于是就有了本系列文章。
GitHub：https://github.com/kwwwvagaa/NetWinformControl
码云：https://gitee.com/kwwwvagaa/net_winform_custom_control.git
如果觉得写的还行，请点个 star 支持一下吧
欢迎前来交流探讨： 企鹅群568015492 
麻烦博客下方点个【推荐】，谢谢
NuGet
Install-Package HZH_Controls
目录
https://blog.csdn.net/kwwwvagaa/article/details/100586547
用处及效果
目前支持ScrollableControl，TreeView，TextBox的滚动条，只需要在相应的界面上添加组件ScrollbarComponent即可
准备工作
用到了（一）c#Winform自定义控件-基类控件 ，如果你还不了解，可以先去看一下
自定义滚动条有2种方式，1：拦截windows消息，重绘，2：做一个新的，盖上去挡着，这里我们采用的是第二种。
开始
添加一个类UCVScrollbar，继承UCControlBase
一些属性
1 /// <summary>
2 /// The mo large change
3 /// </summary>
4 protected int moLargeChange = 10;
5 /// <summary>
6 /// The mo small change
7 /// </summary>
8 protected int moSmallChange = 1;
9 /// <summary>
10 /// The mo minimum
11 /// </summary>
12 protected int moMinimum = 0;
13 /// <summary>
14 /// The mo maximum
15 /// </summary>
16 protected int moMaximum = 100;
17 /// <summary>
18 /// The mo value
19 /// </summary>
20 protected int moValue = 0;
21 /// <summary>
22 /// The n click point
23 /// </summary>
24 private int nClickPoint;
25 /// <summary>
26 /// The mo thumb top
27 /// </summary>
28 protected int moThumbTop = 0;
29 /// <summary>
30 /// The mo automatic size
31 /// </summary>
32 protected bool moAutoSize = false;
33 /// <summary>
34 /// The mo thumb down
35 /// </summary>
36 private bool moThumbDown = false;
37 /// <summary>
38 /// The mo thumb dragging
39 /// </summary>
40 private bool moThumbDragging = false;
41 /// <summary>
42 /// Occurs when [scroll].
43 /// </summary>
44 public new event EventHandler Scroll = null;
45 /// <summary>
46 /// Occurs when [value changed].
47 /// </summary>
48 public event EventHandler ValueChanged = null;
49
50 /// <summary>
51 /// The BTN height
52 /// </summary>
53 private int btnHeight = 18;
54 /// <summary>
55 /// The m int thumb minimum height
56 /// </summary>
57 private int m_intThumbMinHeight = 15;
58
59 /// <summary>
60 /// Gets or sets the height of the BTN.
61 /// </summary>
62 /// <value>The height of the BTN.</value>
63 public int BtnHeight
64 {
65 get { return btnHeight; }
66 set { btnHeight = value; }
67 }
68 /// <summary>
69 /// Gets or sets the large change.
70 /// </summary>
71 /// <value>The large change.</value>
72 [EditorBrowsable(EditorBrowsableState.Always), Browsable(true), DefaultValue(false), Category("自定义"), Description("LargeChange")]
73 public int LargeChange
74 {
75 get { return moLargeChange; }
76 set
77 {
78 moLargeChange = value;
79 Invalidate();
80 }
81 }
82
83 /// <summary>
84 /// Gets or sets the small change.
85 /// </summary>
86 /// <value>The small change.</value>
87 [EditorBrowsable(EditorBrowsableState.Always), Browsable(true), DefaultValue(false), Category("自定义"), Description("SmallChange")]
88 public int SmallChange
89 {
90 get { return moSmallChange; }
91 set
92 {
93 moSmallChange = value;
94 Invalidate();
95 }
96 }
97
98 /// <summary>
99 /// Gets or sets the minimum.
100 /// </summary>
101 /// <value>The minimum.</value>
102 [EditorBrowsable(EditorBrowsableState.Always), Browsable(true), DefaultValue(false), Category("自定义"), Description("Minimum")]
103 public int Minimum
104 {
105 get { return moMinimum; }
106 set
107 {
108 moMinimum = value;
109 Invalidate();
110 }
111 }
112
113 /// <summary>
114 /// Gets or sets the maximum.
115 /// </summary>
116 /// <value>The maximum.</value>
117 [EditorBrowsable(EditorBrowsableState.Always), Browsable(true), DefaultValue(false), Category("自定义"), Description("Maximum")]
118 public int Maximum
119 {
120 get { return moMaximum; }
121 set
122 {
123 moMaximum = value;
124 Invalidate();
125 }
126 }
127
128 /// <summary>
129 /// Gets or sets the value.
130 /// </summary>
131 /// <value>The value.</value>
132 [EditorBrowsable(EditorBrowsableState.Always), Browsable(true), DefaultValue(false), Category("自定义"), Description("Value")]
133 public int Value
134 {
135 get { return moValue; }
136 set
137 {
138 moValue = value;
139
140 int nTrackHeight = (this.Height - btnHeight * 2);
141 float fThumbHeight = ((float)LargeChange / (float)Maximum) * nTrackHeight;
142 int nThumbHeight = (int)fThumbHeight;
143
144 if (nThumbHeight > nTrackHeight)
145 {
146 nThumbHeight = nTrackHeight;
147 fThumbHeight = nTrackHeight;
148 }
149 if (nThumbHeight < m_intThumbMinHeight)
150 {
151 nThumbHeight = m_intThumbMinHeight;
152 fThumbHeight = m_intThumbMinHeight;
153 }
154
155 //figure out value
156 int nPixelRange = nTrackHeight - nThumbHeight;
157 int nRealRange = (Maximum - Minimum) - LargeChange;
158 float fPerc = 0.0f;
159 if (nRealRange != 0)
160 {
161 fPerc = (float)moValue / (float)nRealRange;
162
163 }
164
165 float fTop = fPerc * nPixelRange;
166 moThumbTop = (int)fTop;
167
168
169 Invalidate();
170 }
171 }
172
173 /// <summary>
174 /// Gets or sets a value indicating whether [automatic size].
175 /// </summary>
176 /// <value><c>true</c> if [automatic size]; otherwise, <c>false</c>.</value>
177 public override bool AutoSize
178 {
179 get
180 {
181 return base.AutoSize;
182 }
183 set
184 {
185 base.AutoSize = value;
186 if (base.AutoSize)
187 {
188 this.Width = 15;
189 }
190 }
191 }
192
193 /// <summary>
194 /// The thumb color
195 /// </summary>
196 private Color thumbColor = Color.FromArgb(255, 77, 58);
197
198 /// <summary>
199 /// Gets or sets the color of the thumb.
200 /// </summary>
201 /// <value>The color of the thumb.</value>
202 public Color ThumbColor
203 {
204 get { return thumbColor; }
205 set { thumbColor = value; }
206 }
重绘
1 protected override void OnPaint(PaintEventArgs e)
2 {
3 base.OnPaint(e);
4 e.Graphics.SetGDIHigh();
5
6 //draw thumb
7 int nTrackHeight = (this.Height - btnHeight * 2);
8 float fThumbHeight = ((float)LargeChange / (float)Maximum) * nTrackHeight;
9 int nThumbHeight = (int)fThumbHeight;
10
11 if (nThumbHeight > nTrackHeight)
12 {
13 nThumbHeight = nTrackHeight;
14 fThumbHeight = nTrackHeight;
15 }
16 if (nThumbHeight < m_intThumbMinHeight)
17 {
18 nThumbHeight = m_intThumbMinHeight;
19 fThumbHeight = m_intThumbMinHeight;
20 }
21 int nTop = moThumbTop;
22 nTop += btnHeight;
23 e.Graphics.FillPath(new SolidBrush(thumbColor), new Rectangle(1, nTop, this.Width - 3, nThumbHeight).CreateRoundedRectanglePath(this.ConerRadius));
24
25 ControlHelper.PaintTriangle(e.Graphics, new SolidBrush(thumbColor), new Point(this.Width / 2, btnHeight - Math.Min(5, this.Width / 2)), Math.Min(5, this.Width / 2), GraphDirection.Upward);
26 ControlHelper.PaintTriangle(e.Graphics, new SolidBrush(thumbColor), new Point(this.Width / 2, this.Height - (btnHeight - Math.Min(5, this.Width / 2))), Math.Min(5, this.Width / 2), GraphDirection.Downward);
27
28 }
处理下鼠标事件
1 /// <summary>
2 /// Handles the MouseDown event of the CustomScrollbar control.
3 /// </summary>
4 /// <param name="sender">The source of the event.</param>
5 /// <param name="e">The <see cref="MouseEventArgs"/> instance containing the event data.</param>
6 private void CustomScrollbar_MouseDown(object sender, MouseEventArgs e)
7 {
8 Point ptPoint = this.PointToClient(Cursor.Position);
9 int nTrackHeight = (this.Height - btnHeight * 2);
10 float fThumbHeight = ((float)LargeChange / (float)Maximum) * nTrackHeight;
11 int nThumbHeight = (int)fThumbHeight;
12
13 if (nThumbHeight > nTrackHeight)
14 {
15 nThumbHeight = nTrackHeight;
16 fThumbHeight = nTrackHeight;
17 }
18 if (nThumbHeight < m_intThumbMinHeight)
19 {
20 nThumbHeight = m_intThumbMinHeight;
21 fThumbHeight = m_intThumbMinHeight;
22 }
23
24 int nTop = moThumbTop;
25 nTop += btnHeight;
26
27
28 Rectangle thumbrect = new Rectangle(new Point(1, nTop), new Size(this.Width - 2, nThumbHeight));
29 if (thumbrect.Contains(ptPoint))
30 {
31
32 //hit the thumb
33 nClickPoint = (ptPoint.Y - nTop);
34 //MessageBox.Show(Convert.ToString((ptPoint.Y - nTop)));
35 this.moThumbDown = true;
36 }
37
38 Rectangle uparrowrect = new Rectangle(new Point(1, 0), new Size(this.Width, btnHeight));
39 if (uparrowrect.Contains(ptPoint))
40 {
41
42 int nRealRange = (Maximum - Minimum) - LargeChange;
43 int nPixelRange = (nTrackHeight - nThumbHeight);
44 if (nRealRange > 0)
45 {
46 if (nPixelRange > 0)
47 {
48 if ((moThumbTop - SmallChange) < 0)
49 moThumbTop = 0;
50 else
51 moThumbTop -= SmallChange;
52
53 //figure out value
54 float fPerc = (float)moThumbTop / (float)nPixelRange;
55 float fValue = fPerc * (Maximum - LargeChange);
56
57 moValue = (int)fValue;
58
59 if (ValueChanged != null)
60 ValueChanged(this, new EventArgs());
61
62 if (Scroll != null)
63 Scroll(this, new EventArgs());
64
65 Invalidate();
66 }
67 }
68 }
69
70 Rectangle downarrowrect = new Rectangle(new Point(1, btnHeight + nTrackHeight), new Size(this.Width, btnHeight));
71 if (downarrowrect.Contains(ptPoint))
72 {
73 int nRealRange = (Maximum - Minimum) - LargeChange;
74 int nPixelRange = (nTrackHeight - nThumbHeight);
75 if (nRealRange > 0)
76 {
77 if (nPixelRange > 0)
78 {
79 if ((moThumbTop + SmallChange) > nPixelRange)
80 moThumbTop = nPixelRange;
81 else
82 moThumbTop += SmallChange;
83
84 //figure out value
85 float fPerc = (float)moThumbTop / (float)nPixelRange;
86 float fValue = fPerc * (Maximum - LargeChange);
87
88 moValue = (int)fValue;
89
90 if (ValueChanged != null)
91 ValueChanged(this, new EventArgs());
92
93 if (Scroll != null)
94 Scroll(this, new EventArgs());
95
96 Invalidate();
97 }
98 }
99 }
100 }
101
102 /// <summary>
103 /// Handles the MouseUp event of the CustomScrollbar control.
104 /// </summary>
105 /// <param name="sender">The source of the event.</param>
106 /// <param name="e">The <see cref="MouseEventArgs"/> instance containing the event data.</param>
107 private void CustomScrollbar_MouseUp(object sender, MouseEventArgs e)
108 {
109 this.moThumbDown = false;
110 this.moThumbDragging = false;
111 }
112
113 /// <summary>
114 /// Moves the thumb.
115 /// </summary>
116 /// <param name="y">The y.</param>
117 private void MoveThumb(int y)
118 {
119 int nRealRange = Maximum - Minimum;
120 int nTrackHeight = (this.Height - btnHeight * 2);
121 float fThumbHeight = ((float)LargeChange / (float)Maximum) * nTrackHeight;
122 int nThumbHeight = (int)fThumbHeight;
123
124 if (nThumbHeight > nTrackHeight)
125 {
126 nThumbHeight = nTrackHeight;
127 fThumbHeight = nTrackHeight;
128 }
129 if (nThumbHeight < m_intThumbMinHeight)
130 {
131 nThumbHeight = m_intThumbMinHeight;
132 fThumbHeight = m_intThumbMinHeight;
133 }
134
135 int nSpot = nClickPoint;
136
137 int nPixelRange = (nTrackHeight - nThumbHeight);
138 if (moThumbDown && nRealRange > 0)
139 {
140 if (nPixelRange > 0)
141 {
142 int nNewThumbTop = y - (btnHeight + nSpot);
143
144 if (nNewThumbTop < 0)
145 {
146 moThumbTop = nNewThumbTop = 0;
147 }
148 else if (nNewThumbTop > nPixelRange)
149 {
150 moThumbTop = nNewThumbTop = nPixelRange;
151 }
152 else
153 {
154 moThumbTop = y - (btnHeight + nSpot);
155 }
156
157
158 float fPerc = (float)moThumbTop / (float)nPixelRange;
159 float fValue = fPerc * (Maximum - LargeChange);
160 moValue = (int)fValue;
161
162 Application.DoEvents();
163
164 Invalidate();
165 }
166 }
167 }
168
169 /// <summary>
170 /// Handles the MouseMove event of the CustomScrollbar control.
171 /// </summary>
172 /// <param name="sender">The source of the event.</param>
173 /// <param name="e">The <see cref="MouseEventArgs"/> instance containing the event data.</param>
174 private void CustomScrollbar_MouseMove(object sender, MouseEventArgs e)
175 {
176 if (!moThumbDown)
177 return;
178
179 if (moThumbDown == true)
180 {
181 this.moThumbDragging = true;
182 }
183
184 if (this.moThumbDragging)
185 {
186 MoveThumb(e.Y);
187 }
188
189 if (ValueChanged != null)
190 ValueChanged(this, new EventArgs());
191
192 if (Scroll != null)
193 Scroll(this, new EventArgs());
194 }
完整代码
// ***********************************************************************
// Assembly : HZH_Controls
// Created : 2019-09-19
//
// ***********************************************************************
// <copyright file="UCVScrollbar.cs">
// Copyright by Huang Zhenghui(黄正辉) All, QQ group:568015492 QQ:623128629 Email:623128629@qq.com
// </copyright>
//
// Blog: https://www.cnblogs.com/bfyx
// GitHub：https://github.com/kwwwvagaa/NetWinformControl
// gitee：https://gitee.com/kwwwvagaa/net_winform_custom_control.git
//
// If you use this code, please keep this note.
// ***********************************************************************
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Drawing;
using System.Data;
using System.Text;
using System.Windows.Forms;
using System.Windows.Forms.Design;
using System.Diagnostics;
namespace HZH_Controls.Controls
{
/// <summary>
/// Class UCVScrollbar.
/// Implements the <see cref="HZH_Controls.Controls.UCControlBase" />
/// </summary>
/// <seealso cref="HZH_Controls.Controls.UCControlBase" />
[Designer(typeof(ScrollbarControlDesigner))]
[DefaultEvent("Scroll")]
public class UCVScrollbar : UCControlBase
{
/// <summary>
/// The mo large change
/// </summary>
protected int moLargeChange = 10;
/// <summary>
/// The mo small change
/// </summary>
protected int moSmallChange = 1;
/// <summary>
/// The mo minimum
/// </summary>
protected int moMinimum = 0;
/// <summary>
/// The mo maximum
/// </summary>
protected int moMaximum = 100;
/// <summary>
/// The mo value
/// </summary>
protected int moValue = 0;
/// <summary>
/// The n click point
/// </summary>
private int nClickPoint;
/// <summary>
/// The mo thumb top
/// </summary>
protected int moThumbTop = 0;
/// <summary>
/// The mo automatic size
/// </summary>
protected bool moAutoSize = false;
/// <summary>
/// The mo thumb down
/// </summary>
private bool moThumbDown = false;
/// <summary>
/// The mo thumb dragging
/// </summary>
private bool moThumbDragging = false;
/// <summary>
/// Occurs when [scroll].
/// </summary>
public new event EventHandler Scroll = null;
/// <summary>
/// Occurs when [value changed].
/// </summary>
public event EventHandler ValueChanged = null;
/// <summary>
/// The BTN height
/// </summary>
private int btnHeight = 18;
/// <summary>
/// The m int thumb minimum height
/// </summary>
private int m_intThumbMinHeight = 15;
/// <summary>
/// Gets or sets the height of the BTN.
/// </summary>
/// <value>The height of the BTN.</value>
public int BtnHeight
{
get { return btnHeight; }
set { btnHeight = value; }
}
/// <summary>
/// Gets or sets the large change.
/// </summary>
/// <value>The large change.</value>
[EditorBrowsable(EditorBrowsableState.Always), Browsable(true), DefaultValue(false), Category("自定义"), Description("LargeChange")]
public int LargeChange
{
get { return moLargeChange; }
set
{
moLargeChange = value;
Invalidate();
}
}
/// <summary>
/// Gets or sets the small change.
/// </summary>
/// <value>The small change.</value>
[EditorBrowsable(EditorBrowsableState.Always), Browsable(true), DefaultValue(false), Category("自定义"), Description("SmallChange")]
public int SmallChange
{
get { return moSmallChange; }
set
{
moSmallChange = value;
Invalidate();
}
}
/// <summary>
/// Gets or sets the minimum.
/// </summary>
/// <value>The minimum.</value>
[EditorBrowsable(EditorBrowsableState.Always), Browsable(true), DefaultValue(false), Category("自定义"), Description("Minimum")]
public int Minimum
{
get { return moMinimum; }
set
{
moMinimum = value;
Invalidate();
}
}
/// <summary>
/// Gets or sets the maximum.
/// </summary>
/// <value>The maximum.</value>
[EditorBrowsable(EditorBrowsableState.Always), Browsable(true), DefaultValue(false), Category("自定义"), Description("Maximum")]
public int Maximum
{
get { return moMaximum; }
set
{
moMaximum = value;
Invalidate();
}
}
/// <summary>
/// Gets or sets the value.
/// </summary>
/// <value>The value.</value>
[EditorBrowsable(EditorBrowsableState.Always), Browsable(true), DefaultValue(false), Category("自定义"), Description("Value")]
public int Value
{
get { return moValue; }
set
{
moValue = value;
int nTrackHeight = (this.Height - btnHeight * 2);
float fThumbHeight = ((float)LargeChange / (float)Maximum) * nTrackHeight;
int nThumbHeight = (int)fThumbHeight;
if (nThumbHeight > nTrackHeight)
{
nThumbHeight = nTrackHeight;
fThumbHeight = nTrackHeight;
}
if (nThumbHeight < m_intThumbMinHeight)
{
nThumbHeight = m_intThumbMinHeight;
fThumbHeight = m_intThumbMinHeight;
}
//figure out value
int nPixelRange = nTrackHeight - nThumbHeight;
int nRealRange = (Maximum - Minimum) - LargeChange;
float fPerc = 0.0f;
if (nRealRange != 0)
{
fPerc = (float)moValue / (float)nRealRange;
}
float fTop = fPerc * nPixelRange;
moThumbTop = (int)fTop;
Invalidate();
}
}
/// <summary>
/// Gets or sets a value indicating whether [automatic size].
/// </summary>
/// <value><c>true</c> if [automatic size]; otherwise, <c>false</c>.</value>
public override bool AutoSize
{
get
{
return base.AutoSize;
}
set
{
base.AutoSize = value;
if (base.AutoSize)
{
this.Width = 15;
}
}
}
/// <summary>
/// The thumb color
/// </summary>
private Color thumbColor = Color.FromArgb(255, 77, 58);
/// <summary>
/// Gets or sets the color of the thumb.
/// </summary>
/// <value>The color of the thumb.</value>
public Color ThumbColor
{
get { return thumbColor; }
set { thumbColor = value; }
}
/// <summary>
/// Initializes a new instance of the <see cref="UCVScrollbar"/> class.
/// </summary>
public UCVScrollbar()
{
InitializeComponent();
ConerRadius = 2;
FillColor = Color.FromArgb(239, 239, 239);
IsShowRect = false;
IsRadius = true;
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);
}
/// <summary>
/// 引发 <see cref="E:System.Windows.Forms.Control.Paint" /> 事件。
/// </summary>
/// <param name="e">包含事件数据的 <see cref="T:System.Windows.Forms.PaintEventArgs" />。</param>
protected override void OnPaint(PaintEventArgs e)
{
base.OnPaint(e);
e.Graphics.SetGDIHigh();
//draw thumb
int nTrackHeight = (this.Height - btnHeight * 2);
float fThumbHeight = ((float)LargeChange / (float)Maximum) * nTrackHeight;
int nThumbHeight = (int)fThumbHeight;
if (nThumbHeight > nTrackHeight)
{
nThumbHeight = nTrackHeight;
fThumbHeight = nTrackHeight;
}
if (nThumbHeight < m_intThumbMinHeight)
{
nThumbHeight = m_intThumbMinHeight;
fThumbHeight = m_intThumbMinHeight;
}
int nTop = moThumbTop;
nTop += btnHeight;
e.Graphics.FillPath(new SolidBrush(thumbColor), new Rectangle(1, nTop, this.Width - 3, nThumbHeight).CreateRoundedRectanglePath(this.ConerRadius));
ControlHelper.PaintTriangle(e.Graphics, new SolidBrush(thumbColor), new Point(this.Width / 2, btnHeight - Math.Min(5, this.Width / 2)), Math.Min(5, this.Width / 2), GraphDirection.Upward);
ControlHelper.PaintTriangle(e.Graphics, new SolidBrush(thumbColor), new Point(this.Width / 2, this.Height - (btnHeight - Math.Min(5, this.Width / 2))), Math.Min(5, this.Width / 2), GraphDirection.Downward);
}
/// <summary>
/// Initializes the component.
/// </summary>
private void InitializeComponent()
{
this.SuspendLayout();
//
// UCVScrollbar
//
this.MinimumSize = new System.Drawing.Size(10, 0);
this.Name = "UCVScrollbar";
this.Size = new System.Drawing.Size(18, 150);
this.MouseDown += new System.Windows.Forms.MouseEventHandler(this.CustomScrollbar_MouseDown);
this.MouseMove += new System.Windows.Forms.MouseEventHandler(this.CustomScrollbar_MouseMove);
this.MouseUp += new System.Windows.Forms.MouseEventHandler(this.CustomScrollbar_MouseUp);
this.ResumeLayout(false);
}
/// <summary>
/// Handles the MouseDown event of the CustomScrollbar control.
/// </summary>
/// <param name="sender">The source of the event.</param>
/// <param name="e">The <see cref="MouseEventArgs"/> instance containing the event data.</param>
private void CustomScrollbar_MouseDown(object sender, MouseEventArgs e)
{
Point ptPoint = this.PointToClient(Cursor.Position);
int nTrackHeight = (this.Height - btnHeight * 2);
float fThumbHeight = ((float)LargeChange / (float)Maximum) * nTrackHeight;
int nThumbHeight = (int)fThumbHeight;
if (nThumbHeight > nTrackHeight)
{
nThumbHeight = nTrackHeight;
fThumbHeight = nTrackHeight;
}
if (nThumbHeight < m_intThumbMinHeight)
{
nThumbHeight = m_intThumbMinHeight;
fThumbHeight = m_intThumbMinHeight;
}
int nTop = moThumbTop;
nTop += btnHeight;
Rectangle thumbrect = new Rectangle(new Point(1, nTop), new Size(this.Width - 2, nThumbHeight));
if (thumbrect.Contains(ptPoint))
{
//hit the thumb
nClickPoint = (ptPoint.Y - nTop);
//MessageBox.Show(Convert.ToString((ptPoint.Y - nTop)));
this.moThumbDown = true;
}
Rectangle uparrowrect = new Rectangle(new Point(1, 0), new Size(this.Width, btnHeight));
if (uparrowrect.Contains(ptPoint))
{
int nRealRange = (Maximum - Minimum) - LargeChange;
int nPixelRange = (nTrackHeight - nThumbHeight);
if (nRealRange > 0)
{
if (nPixelRange > 0)
{
if ((moThumbTop - SmallChange) < 0)
moThumbTop = 0;
else
moThumbTop -= SmallChange;
//figure out value
float fPerc = (float)moThumbTop / (float)nPixelRange;
float fValue = fPerc * (Maximum - LargeChange);
moValue = (int)fValue;
if (ValueChanged != null)
ValueChanged(this, new EventArgs());
if (Scroll != null)
Scroll(this, new EventArgs());
Invalidate();
}
}
}
Rectangle downarrowrect = new Rectangle(new Point(1, btnHeight + nTrackHeight), new Size(this.Width, btnHeight));
if (downarrowrect.Contains(ptPoint))
{
int nRealRange = (Maximum - Minimum) - LargeChange;
int nPixelRange = (nTrackHeight - nThumbHeight);
if (nRealRange > 0)
{
if (nPixelRange > 0)
{
if ((moThumbTop + SmallChange) > nPixelRange)
moThumbTop = nPixelRange;
else
moThumbTop += SmallChange;
//figure out value
float fPerc = (float)moThumbTop / (float)nPixelRange;
float fValue = fPerc * (Maximum - LargeChange);
moValue = (int)fValue;
if (ValueChanged != null)
ValueChanged(this, new EventArgs());
if (Scroll != null)
Scroll(this, new EventArgs());
Invalidate();
}
}
}
}
/// <summary>
/// Handles the MouseUp event of the CustomScrollbar control.
/// </summary>
/// <param name="sender">The source of the event.</param>
/// <param name="e">The <see cref="MouseEventArgs"/> instance containing the event data.</param>
private void CustomScrollbar_MouseUp(object sender, MouseEventArgs e)
{
this.moThumbDown = false;
this.moThumbDragging = false;
}
/// <summary>
/// Moves the thumb.
/// </summary>
/// <param name="y">The y.</param>
private void MoveThumb(int y)
{
int nRealRange = Maximum - Minimum;
int nTrackHeight = (this.Height - btnHeight * 2);
float fThumbHeight = ((float)LargeChange / (float)Maximum) * nTrackHeight;
int nThumbHeight = (int)fThumbHeight;
if (nThumbHeight > nTrackHeight)
{
nThumbHeight = nTrackHeight;
fThumbHeight = nTrackHeight;
}
if (nThumbHeight < m_intThumbMinHeight)
{
nThumbHeight = m_intThumbMinHeight;
fThumbHeight = m_intThumbMinHeight;
}
int nSpot = nClickPoint;
int nPixelRange = (nTrackHeight - nThumbHeight);
if (moThumbDown && nRealRange > 0)
{
if (nPixelRange > 0)
{
int nNewThumbTop = y - (btnHeight + nSpot);
if (nNewThumbTop < 0)
{
moThumbTop = nNewThumbTop = 0;
}
else if (nNewThumbTop > nPixelRange)
{
moThumbTop = nNewThumbTop = nPixelRange;
}
else
{
moThumbTop = y - (btnHeight + nSpot);
}
float fPerc = (float)moThumbTop / (float)nPixelRange;
float fValue = fPerc * (Maximum - LargeChange);
moValue = (int)fValue;
Application.DoEvents();
Invalidate();
}
}
}
/// <summary>
/// Handles the MouseMove event of the CustomScrollbar control.
/// </summary>
/// <param name="sender">The source of the event.</param>
/// <param name="e">The <see cref="MouseEventArgs"/> instance containing the event data.</param>
private void CustomScrollbar_MouseMove(object sender, MouseEventArgs e)
{
if (!moThumbDown)
return;
if (moThumbDown == true)
{
this.moThumbDragging = true;
}
if (this.moThumbDragging)
{
MoveThumb(e.Y);
}
if (ValueChanged != null)
ValueChanged(this, new EventArgs());
if (Scroll != null)
Scroll(this, new EventArgs());
}
}
/// <summary>
/// Class ScrollbarControlDesigner.
/// Implements the <see cref="System.Windows.Forms.Design.ControlDesigner" />
/// </summary>
/// <seealso cref="System.Windows.Forms.Design.ControlDesigner" />
internal class ScrollbarControlDesigner : System.Windows.Forms.Design.ControlDesigner
{
/// <summary>
/// 获取指示组件的移动功能的选择规则。
/// </summary>
/// <value>The selection rules.</value>
public override SelectionRules SelectionRules
{
get
{
SelectionRules selectionRules = base.SelectionRules;
PropertyDescriptor propDescriptor = TypeDescriptor.GetProperties(this.Component)["AutoSize"];
if (propDescriptor != null)
{
bool autoSize = (bool)propDescriptor.GetValue(this.Component);
if (autoSize)
{
selectionRules = SelectionRules.Visible | SelectionRules.Moveable | SelectionRules.BottomSizeable | SelectionRules.TopSizeable;
}
else
{
selectionRules = SelectionRules.Visible | SelectionRules.AllSizeable | SelectionRules.Moveable;
}
}
return selectionRules;
}
}
}
}
为了方便使用，我们添加一个组件
新增类ScrollbarComponent，继承 Component, IExtenderProvider
实现接口方法
1 public bool CanExtend(object extendee)
2 {
3 if (extendee is ScrollableControl)
4 {
5 ScrollableControl control = (ScrollableControl)extendee;
6 if (control.AutoScroll == true)
7 {
8 return true;
9 }
10 }
11 else if (extendee is TreeView)
12 {
13 TreeView control = (TreeView)extendee;
14 if (control.Scrollable)
15 {
16 return true;
17 }
18 }
19 else if (extendee is TextBox)
20 {
21 TextBox control = (TextBox)extendee;
22 if (control.Multiline && control.ScrollBars != ScrollBars.None)
23 {
24 return true;
25 }
26 }
27 return false;
28 }
扩展控件属性
1 [Browsable(true), Category("自定义属性"), Description("是否使用自定义滚动条"), DisplayName("UserCustomScrollbar"), Localizable(true)]
2 public bool GetUserCustomScrollbar(Control control)
3 {
4 return m_blnUserCustomScrollbar;
5 }
6
7 public void SetUserCustomScrollbar(Control control, bool blnUserCustomScrollbar)
8 {
9 m_blnUserCustomScrollbar = blnUserCustomScrollbar;
10 control.VisibleChanged += control_VisibleChanged;
11 control.SizeChanged += control_SizeChanged;
12 control.LocationChanged += control_LocationChanged;
13 control.Disposed += control_Disposed;
14
15 if (control is TreeView)
16 {
17 TreeView tv = (TreeView)control;
18 tv.MouseWheel += tv_MouseWheel;
19 tv.AfterSelect += tv_AfterSelect;
20 tv.AfterExpand += tv_AfterExpand;
21 tv.AfterCollapse += tv_AfterCollapse;
22 }
23 else if (control is TextBox)
24 {
25 TextBox txt = (TextBox)control;
26 txt.MouseWheel += txt_MouseWheel;
27 txt.TextChanged += txt_TextChanged;
28
29 txt.KeyDown += txt_KeyDown;
30 }
31 control_SizeChanged(control, null);
32 }
33
处理一下控件什么时候添加滚动条，什么时候移除滚动条，以及滚动条位置大小的改变等
1 void control_Disposed(object sender, EventArgs e)
2 {
3 Control control = (Control)sender;
4 if (m_lstVCache.ContainsKey(control) && m_lstVCache[control].Parent != null)
5 {
6 m_lstVCache[control].Parent.Controls.Remove(m_lstVCache[control]);
7 m_lstVCache.Remove(control);
8 }
9 }
10
11 void control_LocationChanged(object sender, EventArgs e)
12 {
13 ResetVScrollLocation(sender);
14 }
15
16 void control_SizeChanged(object sender, EventArgs e)
17 {
18 if (ControlHelper.IsDesignMode())
19 {
20 return;
21 }
22 else
23 {
24 var control = sender as Control;
25
26 bool blnHasVScrollbar = control.IsHandleCreated && (ControlHelper.GetWindowLong(control.Handle, STYLE) & VSCROLL) != 0;
27 bool blnHasHScrollbar = control.IsHandleCreated && (ControlHelper.GetWindowLong(control.Handle, STYLE) & HSCROLL) != 0;
28 if (blnHasVScrollbar)
29 {
30 if (!m_lstVCache.ContainsKey(control))
31 {
32 if (control.Parent != null)
33 {
34 UCVScrollbar barV = new UCVScrollbar();
35 barV.Scroll += barV_Scroll;
36 m_lstVCache[control] = barV;
37 if (blnHasHScrollbar)
38 {
39 barV.Height = control.Height - barV.Width - 2;
40 }
41 else
42 {
43 barV.Height = control.Height - 2;
44 }
45 SetVMaxNum(control);
46 barV.Location = new System.Drawing.Point(control.Right - barV.Width - 1, control.Top + 1);
47 control.Parent.Controls.Add(barV);
48 int intControlIndex = control.Parent.Controls.GetChildIndex(control);
49 control.Parent.Controls.SetChildIndex(barV, intControlIndex);
50 }
51 }
52 else
53 {
54 SetVMaxNum(control);
55 }
56 }
57 else
58 {
59 if (m_lstVCache.ContainsKey(control) && m_lstVCache[control].Parent != null)
60 {
61 m_lstVCache[control].Parent.Controls.Remove(m_lstVCache[control]);
62 m_lstVCache.Remove(control);
63 }
64 }
65
66 //if (blnHasHScrollbar)
67 //{
68 // if (control.Parent != null)
69 // {
70
71 // }
72 //}
73 //else
74 //{
75 // if (m_lstHCache.ContainsKey(control))
76 // {
77 // if (m_lstHCache[control].Visible)
78 // {
79 // m_lstHCache[control].Parent.Controls.Remove(m_lstHCache[control]);
80 // }
81 // }
82 //}
83 }
84 ResetVScrollLocation(sender);
85 }
86
87 private void SetVMaxNum(Control control)
88 {
89 if (!m_lstVCache.ContainsKey(control))
90 return;
91 UCVScrollbar barV = m_lstVCache[control];
92 if (control is ScrollableControl)
93 {
94 barV.Maximum = (control as ScrollableControl).VerticalScroll.Maximum;
95 barV.Value = (control as ScrollableControl).VerticalScroll.Value;
96 }
97 else if (control is TreeView)
98 {
99 barV.Maximum = GetTreeNodeMaxY(control as TreeView);
100 barV.Value = (control as TreeView).AutoScrollOffset.Y;
101 }
102 else if (control is TextBox)
103 {
104 TextBox txt = (TextBox)control;
105 int intTxtMaxHeight = 0;
106 int intTextHeight = 0;
107 using (var g = txt.CreateGraphics())
108 {
109 intTxtMaxHeight = (int)g.MeasureString(txt.Text, txt.Font).Height;
110 intTextHeight = (int)g.MeasureString(txt.Text.Substring(0, txt.SelectionStart), txt.Font).Height;
111 }
112 barV.Maximum = intTxtMaxHeight;
113 barV.Value = (control as TextBox).AutoScrollOffset.Y;
114 }
115 }
116 /// <summary>
117 /// Resets the v scroll location.
118 /// </summary>
119 /// <param name="sender">The sender.</param>
120 private void ResetVScrollLocation(object sender)
121 {
122 Control control = (Control)sender;
123 bool blnHasVScrollbar = control.IsHandleCreated && (ControlHelper.GetWindowLong(control.Handle, STYLE) & VSCROLL) != 0;
124 bool blnHasHScrollbar = control.IsHandleCreated && (ControlHelper.GetWindowLong(control.Handle, STYLE) & HSCROLL) != 0;
125 if (control.Visible)
126 {
127 if (m_lstVCache.ContainsKey(control))
128 {
129 m_lstVCache[control].Location = new System.Drawing.Point(control.Right - m_lstVCache[control].Width - 1, control.Top + 1);
130 if (blnHasHScrollbar)
131 {
132 m_lstVCache[control].Height = control.Height - m_lstVCache[control].Width - 2;
133 }
134 else
135 {
136 m_lstVCache[control].Height = control.Height - 2;
137 }
138 }
139 }
140 }
141 /// <summary>
142 /// Handles the VisibleChanged event of the control control.
143 /// </summary>
144 /// <param name="sender">The source of the event.</param>
145 /// <param name="e">The <see cref="EventArgs"/> instance containing the event data.</param>
146 void control_VisibleChanged(object sender, EventArgs e)
147 {
148 Control control = (Control)sender;
149 if (!control.Visible)
150 {
151 if (m_lstVCache.ContainsKey(control) && m_lstVCache[control].Parent != null)
152 {
153 m_lstVCache[control].Parent.Controls.Remove(m_lstVCache[control]);
154 m_lstVCache.Remove(control);
155 }
156 }
157 }
158
159 private const int HSCROLL = 0x100000;
160 private const int VSCROLL = 0x200000;
161 private const int STYLE = -16;
162
163 private Dictionary<Control, UCVScrollbar> m_lstVCache = new Dictionary<Control, UCVScrollbar>();
164 //private Dictionary<ScrollableControl, UCVScrollbar> m_lstHCache = new Dictionary<ScrollableControl, UCVScrollbar>();
165
166 void barV_Scroll(object sender, EventArgs e)
167 {
168 UCVScrollbar bar = (UCVScrollbar)sender;
169 if (m_lstVCache.ContainsValue(bar))
170 {
171 Control c = m_lstVCache.FirstOrDefault(p => p.Value == bar).Key;
172 if (c is ScrollableControl)
173 {
174 (c as ScrollableControl).AutoScrollPosition = new Point(0, bar.Value);
175 }
176 else if (c is TreeView)
177 {
178 TreeView tv = (c as TreeView);
179 SetTreeViewScrollLocation(tv, tv.Nodes, bar.Value);
180 }
181 else if (c is TextBox)
182 {
183 TextBox txt = (c as TextBox);
184 SetTextBoxScrollLocation(txt, bar.Value);
185 }
186 }
187 }
188
189 #region Treeview处理 English:Treeview\u5904\u7406
190 void tv_AfterCollapse(object sender, TreeViewEventArgs e)
191 {
192 control_SizeChanged(sender as Control, null);
193 }
194
195 void tv_AfterExpand(object sender, TreeViewEventArgs e)
196 {
197 control_SizeChanged(sender as Control, null);
198 }
199 /// <summary>
200 /// Gets the tree node 最大高度
201 /// </summary>
202 /// <param name="tv">The tv.</param>
203 /// <returns>System.Int32.</returns>
204 private int GetTreeNodeMaxY(TreeView tv)
205 {
206 TreeNode tnLast = tv.Nodes[tv.Nodes.Count - 1];
207 begin:
208 if (tnLast.IsExpanded && tnLast.Nodes.Count > 0)
209 {
210 tnLast = tnLast.LastNode;
211 goto begin;
212 }
213 return tnLast.Bounds.Bottom;
214 }
215 void tv_AfterSelect(object sender, TreeViewEventArgs e)
216 {
217 TreeView tv = (TreeView)sender;
218 if (m_lstVCache.ContainsKey(tv))
219 {
220 m_lstVCache[tv].Value = tv.Nodes.Count > 0 ? Math.Abs(tv.Nodes[0].Bounds.Top) : 0;
221 }
222 }
223
224 void tv_MouseWheel(object sender, MouseEventArgs e)
225 {
226 TreeView tv = (TreeView)sender;
227 if (m_lstVCache.ContainsKey(tv))
228 {
229 m_lstVCache[tv].Value = tv.Nodes.Count > 0 ? Math.Abs(tv.Nodes[0].Bounds.Top) : 0;
230 }
231 }
232 /// <summary>
233 /// Sets the TreeView scroll location.
234 /// </summary>
235 /// <param name="tv">The tv.</param>
236 /// <param name="tns">The TNS.</param>
237 /// <param name="intY">The int y.</param>
238 /// <returns><c>true</c> if XXXX, <c>false</c> otherwise.</returns>
239 private bool SetTreeViewScrollLocation(TreeView tv, TreeNodeCollection tns, int intY)
240 {
241 for (int i = 0; i < tns.Count; i++)
242 {
243 if (intY >= tns[i].Bounds.Top - tv.Nodes[0].Bounds.Top - 3 && intY <= tns[i].Bounds.Bottom - tv.Nodes[0].Bounds.Top + 3)
244 {
245 tns[i].EnsureVisible();
246 return true;
247 }
248 else if (tns[i].IsExpanded && tns[i].Nodes.Count > 0)
249 {
250 bool bln = SetTreeViewScrollLocation(tv, tns[i].Nodes, intY);
251 if (bln)
252 return true;
253 }
254 }
255 return false;
256 }
257 #endregion
258
259 #region TextBox处理 English:TextBox Processing
260
261 void txt_TextChanged(object sender, EventArgs e)
262 {
263 TextBox txt = sender as TextBox;
264 control_SizeChanged(txt, null);
265 SetVMaxNum(txt);
266 if (m_lstVCache.ContainsKey(txt))
267 {
268 using (var g = txt.CreateGraphics())
269 {
270 var size = g.MeasureString(txt.Text.Substring(0, txt.SelectionStart), txt.Font);
271 m_lstVCache[txt].Value = (int)size.Height;
272 }
273 }
274 }
275 private void SetTextBoxScrollLocation(TextBox txt, int intY)
276 {
277 using (var g = txt.CreateGraphics())
278 {
279 for (int i = 0; i < txt.Lines.Length; i++)
280 {
281 string str = string.Join("\n", txt.Lines.Take(i + 1));
282 var size = g.MeasureString(str, txt.Font);
283 if (size.Height >= intY)
284 {
285 txt.SelectionStart = str.Length;
286 txt.ScrollToCaret();
287 return;
288 }
289 }
290 }
291 }
292
293 void txt_KeyDown(object sender, KeyEventArgs e)
294 {
295 if (e.KeyCode == Keys.Up || e.KeyCode == Keys.Down)
296 {
297 TextBox txt = (TextBox)sender;
298 if (m_lstVCache.ContainsKey(txt))
299 {
300 using (var g = txt.CreateGraphics())
301 {
302 var size = g.MeasureString(txt.Text.Substring(0, txt.SelectionStart), txt.Font);
303 m_lstVCache[txt].Value = (int)size.Height;
304 }
305 }
306 }
307 }
308
309 void txt_MouseWheel(object sender, MouseEventArgs e)
310 {
311 TextBox txt = (TextBox)sender;
312 if (m_lstVCache.ContainsKey(txt))
313 {
314 using (var g = txt.CreateGraphics())
315 {
316 StringBuilder str = new StringBuilder();
317 for (int i = 0; i < System.Windows.Forms.SystemInformation.MouseWheelScrollLines; i++)
318 {
319 str.AppendLine("A");
320 }
321 var height = (int)g.MeasureString(str.ToString(), txt.Font).Height;
322 if (e.Delta < 0)
323 {
324 if (height + m_lstVCache[txt].Value > m_lstVCache[txt].Maximum)
325 m_lstVCache[txt].Value = m_lstVCache[txt].Maximum;
326 else
327 m_lstVCache[txt].Value += height;
328 }
329 else
330 {
331 if (m_lstVCache[txt].Value - height < 0)
332 m_lstVCache[txt].Value = 0;
333 else
334 m_lstVCache[txt].Value -= height;
335 }
336 }
337 }
338 }
339 #endregion
完整代码
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
namespace HZH_Controls.Controls.ScrollBar
{
[ProvideProperty("UserCustomScrollbar", typeof(Control))]
public class ScrollbarComponent : Component, IExtenderProvider
{
public ScrollbarComponent()
{
}
public ScrollbarComponent(IContainer container)
{
container.Add(this);
}
bool m_blnUserCustomScrollbar = true;
public bool CanExtend(object extendee)
{
if (extendee is ScrollableControl)
{
ScrollableControl control = (ScrollableControl)extendee;
if (control.AutoScroll == true)
{
return true;
}
}
else if (extendee is TreeView)
{
TreeView control = (TreeView)extendee;
if (control.Scrollable)
{
return true;
}
}
else if (extendee is TextBox)
{
TextBox control = (TextBox)extendee;
if (control.Multiline && control.ScrollBars != ScrollBars.None)
{
return true;
}
}
return false;
}
[Browsable(true), Category("自定义属性"), Description("是否使用自定义滚动条"), DisplayName("UserCustomScrollbar"), Localizable(true)]
public bool GetUserCustomScrollbar(Control control)
{
return m_blnUserCustomScrollbar;
}
public void SetUserCustomScrollbar(Control control, bool blnUserCustomScrollbar)
{
m_blnUserCustomScrollbar = blnUserCustomScrollbar;
control.VisibleChanged += control_VisibleChanged;
control.SizeChanged += control_SizeChanged;
control.LocationChanged += control_LocationChanged;
control.Disposed += control_Disposed;
if (control is TreeView)
{
TreeView tv = (TreeView)control;
tv.MouseWheel += tv_MouseWheel;
tv.AfterSelect += tv_AfterSelect;
tv.AfterExpand += tv_AfterExpand;
tv.AfterCollapse += tv_AfterCollapse;
}
else if (control is TextBox)
{
TextBox txt = (TextBox)control;
txt.MouseWheel += txt_MouseWheel;
txt.TextChanged += txt_TextChanged;
txt.KeyDown += txt_KeyDown;
}
control_SizeChanged(control, null);
}
void control_Disposed(object sender, EventArgs e)
{
Control control = (Control)sender;
if (m_lstVCache.ContainsKey(control) && m_lstVCache[control].Parent != null)
{
m_lstVCache[control].Parent.Controls.Remove(m_lstVCache[control]);
m_lstVCache.Remove(control);
}
}
void control_LocationChanged(object sender, EventArgs e)
{
ResetVScrollLocation(sender);
}
void control_SizeChanged(object sender, EventArgs e)
{
if (ControlHelper.IsDesignMode())
{
return;
}
else
{
var control = sender as Control;
bool blnHasVScrollbar = control.IsHandleCreated && (ControlHelper.GetWindowLong(control.Handle, STYLE) & VSCROLL) != 0;
bool blnHasHScrollbar = control.IsHandleCreated && (ControlHelper.GetWindowLong(control.Handle, STYLE) & HSCROLL) != 0;
if (blnHasVScrollbar)
{
if (!m_lstVCache.ContainsKey(control))
{
if (control.Parent != null)
{
UCVScrollbar barV = new UCVScrollbar();
barV.Scroll += barV_Scroll;
m_lstVCache[control] = barV;
if (blnHasHScrollbar)
{
barV.Height = control.Height - barV.Width - 2;
}
else
{
barV.Height = control.Height - 2;
}
SetVMaxNum(control);
barV.Location = new System.Drawing.Point(control.Right - barV.Width - 1, control.Top + 1);
control.Parent.Controls.Add(barV);
int intControlIndex = control.Parent.Controls.GetChildIndex(control);
control.Parent.Controls.SetChildIndex(barV, intControlIndex);
}
}
else
{
SetVMaxNum(control);
}
}
else
{
if (m_lstVCache.ContainsKey(control) && m_lstVCache[control].Parent != null)
{
m_lstVCache[control].Parent.Controls.Remove(m_lstVCache[control]);
m_lstVCache.Remove(control);
}
}
//if (blnHasHScrollbar)
//{
// if (control.Parent != null)
// {
// }
//}
//else
//{
// if (m_lstHCache.ContainsKey(control))
// {
// if (m_lstHCache[control].Visible)
// {
// m_lstHCache[control].Parent.Controls.Remove(m_lstHCache[control]);
// }
// }
//}
}
ResetVScrollLocation(sender);
}
private void SetVMaxNum(Control control)
{
if (!m_lstVCache.ContainsKey(control))
return;
UCVScrollbar barV = m_lstVCache[control];
if (control is ScrollableControl)
{
barV.Maximum = (control as ScrollableControl).VerticalScroll.Maximum;
barV.Value = (control as ScrollableControl).VerticalScroll.Value;
}
else if (control is TreeView)
{
barV.Maximum = GetTreeNodeMaxY(control as TreeView);
barV.Value = (control as TreeView).AutoScrollOffset.Y;
}
else if (control is TextBox)
{
TextBox txt = (TextBox)control;
int intTxtMaxHeight = 0;
int intTextHeight = 0;
using (var g = txt.CreateGraphics())
{
intTxtMaxHeight = (int)g.MeasureString(txt.Text, txt.Font).Height;
intTextHeight = (int)g.MeasureString(txt.Text.Substring(0, txt.SelectionStart), txt.Font).Height;
}
barV.Maximum = intTxtMaxHeight;
barV.Value = (control as TextBox).AutoScrollOffset.Y;
}
}
/// <summary>
/// Resets the v scroll location.
/// </summary>
/// <param name="sender">The sender.</param>
private void ResetVScrollLocation(object sender)
{
Control control = (Control)sender;
bool blnHasVScrollbar = control.IsHandleCreated && (ControlHelper.GetWindowLong(control.Handle, STYLE) & VSCROLL) != 0;
bool blnHasHScrollbar = control.IsHandleCreated && (ControlHelper.GetWindowLong(control.Handle, STYLE) & HSCROLL) != 0;
if (control.Visible)
{
if (m_lstVCache.ContainsKey(control))
{
m_lstVCache[control].Location = new System.Drawing.Point(control.Right - m_lstVCache[control].Width - 1, control.Top + 1);
if (blnHasHScrollbar)
{
m_lstVCache[control].Height = control.Height - m_lstVCache[control].Width - 2;
}
else
{
m_lstVCache[control].Height = control.Height - 2;
}
}
}
}
/// <summary>
/// Handles the VisibleChanged event of the control control.
/// </summary>
/// <param name="sender">The source of the event.</param>
/// <param name="e">The <see cref="EventArgs"/> instance containing the event data.</param>
void control_VisibleChanged(object sender, EventArgs e)
{
Control control = (Control)sender;
if (!control.Visible)
{
if (m_lstVCache.ContainsKey(control) && m_lstVCache[control].Parent != null)
{
m_lstVCache[control].Parent.Controls.Remove(m_lstVCache[control]);
m_lstVCache.Remove(control);
}
}
}
private const int HSCROLL = 0x100000;
private const int VSCROLL = 0x200000;
private const int STYLE = -16;
private Dictionary<Control, UCVScrollbar> m_lstVCache = new Dictionary<Control, UCVScrollbar>();
//private Dictionary<ScrollableControl, UCVScrollbar> m_lstHCache = new Dictionary<ScrollableControl, UCVScrollbar>();
void barV_Scroll(object sender, EventArgs e)
{
UCVScrollbar bar = (UCVScrollbar)sender;
if (m_lstVCache.ContainsValue(bar))
{
Control c = m_lstVCache.FirstOrDefault(p => p.Value == bar).Key;
if (c is ScrollableControl)
{
(c as ScrollableControl).AutoScrollPosition = new Point(0, bar.Value);
}
else if (c is TreeView)
{
TreeView tv = (c as TreeView);
SetTreeViewScrollLocation(tv, tv.Nodes, bar.Value);
}
else if (c is TextBox)
{
TextBox txt = (c as TextBox);
SetTextBoxScrollLocation(txt, bar.Value);
}
}
}
#region Treeview处理 English:Treeview\u5904\u7406
void tv_AfterCollapse(object sender, TreeViewEventArgs e)
{
control_SizeChanged(sender as Control, null);
}
void tv_AfterExpand(object sender, TreeViewEventArgs e)
{
control_SizeChanged(sender as Control, null);
}
/// <summary>
/// Gets the tree node 最大高度
/// </summary>
/// <param name="tv">The tv.</param>
/// <returns>System.Int32.</returns>
private int GetTreeNodeMaxY(TreeView tv)
{
TreeNode tnLast = tv.Nodes[tv.Nodes.Count - 1];
begin:
if (tnLast.IsExpanded && tnLast.Nodes.Count > 0)
{
tnLast = tnLast.LastNode;
goto begin;
}
return tnLast.Bounds.Bottom;
}
void tv_AfterSelect(object sender, TreeViewEventArgs e)
{
TreeView tv = (TreeView)sender;
if (m_lstVCache.ContainsKey(tv))
{
m_lstVCache[tv].Value = tv.Nodes.Count > 0 ? Math.Abs(tv.Nodes[0].Bounds.Top) : 0;
}
}
void tv_MouseWheel(object sender, MouseEventArgs e)
{
TreeView tv = (TreeView)sender;
if (m_lstVCache.ContainsKey(tv))
{
m_lstVCache[tv].Value = tv.Nodes.Count > 0 ? Math.Abs(tv.Nodes[0].Bounds.Top) : 0;
}
}
/// <summary>
/// Sets the TreeView scroll location.
/// </summary>
/// <param name="tv">The tv.</param>
/// <param name="tns">The TNS.</param>
/// <param name="intY">The int y.</param>
/// <returns><c>true</c> if XXXX, <c>false</c> otherwise.</returns>
private bool SetTreeViewScrollLocation(TreeView tv, TreeNodeCollection tns, int intY)
{
for (int i = 0; i < tns.Count; i++)
{
if (intY >= tns[i].Bounds.Top - tv.Nodes[0].Bounds.Top - 3 && intY <= tns[i].Bounds.Bottom - tv.Nodes[0].Bounds.Top + 3)
{
tns[i].EnsureVisible();
return true;
}
else if (tns[i].IsExpanded && tns[i].Nodes.Count > 0)
{
bool bln = SetTreeViewScrollLocation(tv, tns[i].Nodes, intY);
if (bln)
return true;
}
}
return false;
}
#endregion
#region TextBox处理 English:TextBox Processing
void txt_TextChanged(object sender, EventArgs e)
{
TextBox txt = sender as TextBox;
control_SizeChanged(txt, null);
SetVMaxNum(txt);
if (m_lstVCache.ContainsKey(txt))
{
using (var g = txt.CreateGraphics())
{
var size = g.MeasureString(txt.Text.Substring(0, txt.SelectionStart), txt.Font);
m_lstVCache[txt].Value = (int)size.Height;
}
}
}
private void SetTextBoxScrollLocation(TextBox txt, int intY)
{
using (var g = txt.CreateGraphics())
{
for (int i = 0; i < txt.Lines.Length; i++)
{
string str = string.Join("\n", txt.Lines.Take(i + 1));
var size = g.MeasureString(str, txt.Font);
if (size.Height >= intY)
{
txt.SelectionStart = str.Length;
txt.ScrollToCaret();
return;
}
}
}
}
void txt_KeyDown(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.Up || e.KeyCode == Keys.Down)
{
TextBox txt = (TextBox)sender;
if (m_lstVCache.ContainsKey(txt))
{
using (var g = txt.CreateGraphics())
{
var size = g.MeasureString(txt.Text.Substring(0, txt.SelectionStart), txt.Font);
m_lstVCache[txt].Value = (int)size.Height;
}
}
}
}
void txt_MouseWheel(object sender, MouseEventArgs e)
{
TextBox txt = (TextBox)sender;
if (m_lstVCache.ContainsKey(txt))
{
using (var g = txt.CreateGraphics())
{
StringBuilder str = new StringBuilder();
for (int i = 0; i < System.Windows.Forms.SystemInformation.MouseWheelScrollLines; i++)
{
str.AppendLine("A");
}
var height = (int)g.MeasureString(str.ToString(), txt.Font).Height;
if (e.Delta < 0)
{
if (height + m_lstVCache[txt].Value > m_lstVCache[txt].Maximum)
m_lstVCache[txt].Value = m_lstVCache[txt].Maximum;
else
m_lstVCache[txt].Value += height;
}
else
{
if (m_lstVCache[txt].Value - height < 0)
m_lstVCache[txt].Value = 0;
else
m_lstVCache[txt].Value -= height;
}
}
}
}
#endregion
}
}
代码就这些了
使用的时候，只需要在界面上添加组件ScrollbarComponent即可
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