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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://www.cnblogs.com/bfyx/p/11364884.html
用处及效果
准备工作
依然是用GDI+画的，不懂的可以先百度一下
开始
添加一个实体类，用以记录数据源节点信息
1 public class MindMappingItemEntity
2 {
3 /// <summary>
4 /// Gets or sets the identifier.
5 /// </summary>
6 /// <value>The identifier.</value>
7 public string ID { get; set; }
8 private string _text;
9 /// <summary>
10 /// Gets or sets the text.
11 /// </summary>
12 /// <value>The text.</value>
13 public string Text
14 {
15 get { return _text; }
16 set
17 {
18 _text = value;
19 ResetSize();
20 }
21 }
22 /// <summary>
23 /// Gets or sets the data source.
24 /// </summary>
25 /// <value>The data source.</value>
26 public object DataSource { get; set; }
27 /// <summary>
28 /// The childrens
29 /// </summary>
30 private MindMappingItemEntity[] _Childrens;
31 /// <summary>
32 /// Gets or sets the childrens.
33 /// </summary>
34 /// <value>The childrens.</value>
35 public MindMappingItemEntity[] Childrens
36 {
37 get { return _Childrens; }
38 set
39 {
40 _Childrens = value;
41 if (value != null && value.Length > 0)
42 {
43 value.ToList().ForEach(p => { if (p != null) { p.ParentItem = this; } });
44 }
45 }
46 }
47 /// <summary>
48 /// The back color
49 /// </summary>
50 private Color backColor = Color.Transparent;
51
52 /// <summary>
53 /// Gets or sets the color of the back.
54 /// </summary>
55 /// <value>The color of the back.</value>
56 public Color BackColor
57 {
58 get { return backColor; }
59 set { backColor = value; }
60 }
61
62 private Font font = new Font("微软雅黑", 10);
63
64 public Font Font
65 {
66 get { return font; }
67 set
68 {
69 font = value;
70 ResetSize();
71 }
72 }
73
74 /// <summary>
75 /// The fore color
76 /// </summary>
77 private Color foreColor = Color.Black;
78
79 /// <summary>
80 /// Gets or sets the color of the fore.
81 /// </summary>
82 /// <value>The color of the fore.</value>
83 public Color ForeColor
84 {
85 get { return foreColor; }
86 set { foreColor = value; }
87 }
88 private bool _IsExpansion = false;
89 /// <summary>
90 /// Gets or sets a value indicating whether the instance is expanded.
91 /// </summary>
92 /// <value><c>true</c> if this instance is expansion; otherwise, <c>false</c>.</value>
93 public bool IsExpansion
94 {
95 get
96 {
97 return _IsExpansion;
98 }
99 set
100 {
101 if (value == _IsExpansion)
102 return;
103 _IsExpansion = value;
104 if (!value)
105 {
106 _Childrens.ToList().ForEach(p => { if (p != null) { p.IsExpansion = false; } });
107 }
108
109 }
110 }
111
112 /// <summary>
113 /// Gets the parent item.
114 /// </summary>
115 /// <value>The parent item.</value>
116 public MindMappingItemEntity ParentItem { get; private set; }
117 /// <summary>
118 /// Gets all childrens maximum show count.
119 /// </summary>
120 /// <value>All childrens maximum show count.</value>
121 public int AllChildrensMaxShowHeight { get { return GetAllChildrensMaxShowHeight(); } }
122 /// <summary>
123 /// Gets the maximum level.
124 /// </summary>
125 /// <value>The maximum level.</value>
126 public int AllChildrensMaxShowWidth { get { return GetAllChildrensMaxShowWidth(); } }
127
128 /// <summary>
129 /// Gets all childrens maximum show count.
130 /// </summary>
131 /// <returns>System.Int32.</returns>
132 private int GetAllChildrensMaxShowHeight()
133 {
134 if (!_IsExpansion || _Childrens == null || _Childrens.Length <= 0)
135 return ItemHeight + 10;
136 else
137 {
138 return _Childrens.Sum(p => p == null ? 0 : p.AllChildrensMaxShowHeight);
139 }
140 }
141 /// <summary>
142 /// Gets the maximum level.
143 /// </summary>
144 /// <returns>System.Int32.</returns>
145 private int GetAllChildrensMaxShowWidth()
146 {
147 if (!_IsExpansion || _Childrens == null || _Childrens.Length <= 0)
148 return ItemWidth + 50;
149 else
150 {
151 return 1 + _Childrens.Max(p => p == null ? 0 : p.AllChildrensMaxShowWidth);
152 }
153 }
154 /// <summary>
155 /// Gets or sets the working rectangle.
156 /// </summary>
157 /// <value>The working rectangle.</value>
158 internal RectangleF WorkingRectangle { get; set; }
159 /// <summary>
160 /// Gets or sets the draw rectangle.
161 /// </summary>
162 /// <value>The draw rectangle.</value>
163 internal RectangleF DrawRectangle { get; set; }
164 /// <summary>
165 /// Gets or sets the expansion rectangle.
166 /// </summary>
167 /// <value>The expansion rectangle.</value>
168 internal RectangleF ExpansionRectangle { get; set; }
169 /// <summary>
170 /// Gets the height of the item.
171 /// </summary>
172 /// <value>The height of the item.</value>
173 private int ItemHeight { private get; private set; }
174 /// <summary>
175 /// Gets the width of the item.
176 /// </summary>
177 /// <value>The width of the item.</value>
178 private int ItemWidth { private get; private set; }
179 /// <summary>
180 /// Resets the size.
181 /// </summary>
182 private void ResetSize()
183 {
184 string _t = _text;
185 if (string.IsNullOrEmpty(_t))
186 {
187 _t = "aaaa";
188 }
189 Bitmap bit = new Bitmap(1, 1);
190 var g = Graphics.FromImage(bit);
191 var size = g.MeasureString(_t, font);
192 g.Dispose();
193 bit.Dispose();
194 ItemHeight = (int)size.Height;
195 ItemWidth = (int)size.Width;
196 }
197 }
主要属性说明：
Text：显示文字
Childrens：子节点信息
BackColor：节点颜色
IsExpansion：是否展开子节点
ParentItem：父级节点
AllChildrensMaxShowHeight：该节点包含所有子节点需要显示的高度，通过私有函数GetAllChildrensMaxShowHeight()返回结果
AllChildrensMaxShowWidth：该节点包含所有子节点需要显示的宽度，通过私有函数GetAllChildrensMaxShowWidth()返回结果
WorkingRectangle：该节点以及所有子节点的工作区域
DrawRectangle：该节点的绘制区域
ExpansionRectangle：展开折叠按钮的绘制区域
ItemHeight：该节点的高度
ItemWidth：该节点的宽度
主要函数说明：
GetAllChildrensMaxShowHeight：获取当前节点及所有子节点需要的最大高度
GetAllChildrensMaxShowWidth：获取当前节点及所有子节点需要的最大宽度
ResetSize：当文本和字体改变时重新计算宽高
添加一个类UCMindMapping，继承UserControl
添加一些属性
1 /// <summary>
2 /// The line color
3 /// </summary>
4 private Color lineColor = Color.Black;
5
6 /// <summary>
7 /// Gets or sets the color of the line.
8 /// </summary>
9 /// <value>The color of the line.</value>
10 [Description("线条颜色"), Category("自定义")]
11 public Color LineColor
12 {
13 get { return lineColor; }
14 set
15 {
16 lineColor = value;
17 Refresh();
18 }
19 }
20 /// <summary>
21 /// The split width
22 /// </summary>
23 private int splitWidth = 50;
24 // private int itemHeight = 20;
25 /// <summary>
26 /// The padding
27 /// </summary>
28 private int padding = 20;
29
30 /// <summary>
31 /// The m rect working
32 /// </summary>
33 Rectangle m_rectWorking = Rectangle.Empty;
34 /// <summary>
35 /// Occurs when [item clicked].
36 /// </summary>
37 public event EventHandler ItemClicked;
38 /// <summary>
39 /// The data source
40 /// </summary>
41 private MindMappingItemEntity dataSource;
42 /// <summary>
43 /// Gets or sets the data source.
44 /// </summary>
45 /// <value>The data source.</value>
46 [Description("数据源"), Category("自定义")]
47 public MindMappingItemEntity DataSource
48 {
49 get { return dataSource; }
50 set
51 {
52 dataSource = value;
53
54 ResetSize();
55 }
56 }
一个辅助函数，用以在大小过数据改变时计算工作区域和位置
1 /// <summary>
2 /// 重置大小
3 /// </summary>
4 private void ResetSize()
5 {
6 if (this.Parent == null)
7 return;
8 try
9 {
10 ControlHelper.FreezeControl(this, true);
11 if (dataSource == null)
12 {
13 m_rectWorking = Rectangle.Empty;
14 this.Size = this.Parent.Size;
15 }
16 else
17 {
18 int intWidth = dataSource.AllChildrensMaxShowWidth;
19 int intHeight = dataSource.AllChildrensMaxShowHeight;
20 this.Width = intWidth + padding * 2;
21 this.Height = intHeight + padding * 2;
22 if (this.Width < this.Parent.Width)
23 this.Width = this.Parent.Width;
24 m_rectWorking = new Rectangle(padding, padding, intWidth, intHeight);
25 if (this.Height > this.Parent.Height)
26 {
27 //this.Location = new Point(0, 0);
28 }
29 else
30 this.Location = new Point(0, (this.Parent.Height - this.Height) / 2);
31 }
32 }
33 finally
34 {
35 ControlHelper.FreezeControl(this, false);
36 }
37 }
重绘
1 /// <summary>
2 /// 引发 <see cref="E:System.Windows.Forms.Control.Paint" /> 事件。
3 /// </summary>
4 /// <param name="e">包含事件数据的 <see cref="T:System.Windows.Forms.PaintEventArgs" />。</param>
5 protected override void OnPaint(PaintEventArgs e)
6 {
7 try
8 {
9 base.OnPaint(e);
10 if (m_rectWorking == Rectangle.Empty || m_rectWorking == null)
11 return;
12 var g = e.Graphics;
13 g.SetGDIHigh();
14
15 int intHeight = dataSource.AllChildrensMaxShowHeight;
16 dataSource.WorkingRectangle = new RectangleF(m_rectWorking.Left, m_rectWorking.Top + (m_rectWorking.Height - intHeight) / 2, m_rectWorking.Width, intHeight);
17
18 DrawItem(dataSource, g);
19 }
20 catch (Exception exc)
21 {
22 MessageBox.Show(exc.ToString(), "错误");
23 }
24 }
1 /// <summary>
2 /// 画节点
3 /// </summary>
4 /// <param name="item">The item.</param>
5 /// <param name="g">The g.</param>
6 private void DrawItem(MindMappingItemEntity item, Graphics g)
7 {
8 //节点
9 var size = g.MeasureString(item.Text, item.Font);
10 item.DrawRectangle = new RectangleF(item.WorkingRectangle.Left + 2, item.WorkingRectangle.Top + (item.WorkingRectangle.Height - size.Height) / 2 + 2, size.Width + 4, size.Height + 4);
11 GraphicsPath drawPath = item.DrawRectangle.CreateRoundedRectanglePath(5);
12 g.FillPath(new SolidBrush(item.BackColor), drawPath);
13 g.DrawString(item.Text, item.Font, new SolidBrush(item.ForeColor), item.DrawRectangle.Location.X + 2, item.DrawRectangle.Location.Y + 2);
14 //子节点
15 if (item.Childrens != null && item.IsExpansion)
16 {
17 for (int i = 0; i < item.Childrens.Length; i++)
18 {
19 var child = item.Childrens[i];
20 if (i == 0)
21 {
22 child.WorkingRectangle = new RectangleF(item.DrawRectangle.Right + splitWidth, item.WorkingRectangle.Top, item.WorkingRectangle.Width - (item.DrawRectangle.Width + splitWidth), child.AllChildrensMaxShowHeight);
23 }
24 else
25 {
26 child.WorkingRectangle = new RectangleF(item.DrawRectangle.Right + splitWidth, item.Childrens[i - 1].WorkingRectangle.Bottom, item.WorkingRectangle.Width - (item.DrawRectangle.Width + splitWidth), child.AllChildrensMaxShowHeight);
27 }
28 DrawItem(child, g);
29 }
30 }
31 //连线
32 if (item.ParentItem != null)
33 {
34 g.DrawLines(new Pen(new SolidBrush(lineColor), 1), new PointF[]
35 {
36 new PointF(item.ParentItem.DrawRectangle.Right,item.ParentItem.DrawRectangle.Top+item.ParentItem.DrawRectangle.Height/2),
37 new PointF(item.ParentItem.DrawRectangle.Right+12,item.ParentItem.DrawRectangle.Top+item.ParentItem.DrawRectangle.Height/2),
38 //new PointF(item.ParentItem.DrawRectangle.Right+12,item.DrawRectangle.Top+item.DrawRectangle.Height/2),
39 new PointF(item.DrawRectangle.Left-12,item.DrawRectangle.Top+item.DrawRectangle.Height/2),
40 new PointF(item.DrawRectangle.Left,item.DrawRectangle.Top+item.DrawRectangle.Height/2),
41 });
42 }
43 //展开折叠按钮
44 if (item.Childrens != null && item.Childrens.Length > 0)
45 {
46 RectangleF _rect = new RectangleF(item.DrawRectangle.Right + 1, item.DrawRectangle.Top + (item.DrawRectangle.Height - 10) / 2, 10, 10);
47 item.ExpansionRectangle = _rect;
48 g.FillEllipse(new SolidBrush(this.BackColor), _rect);
49 g.DrawEllipse(new Pen(new SolidBrush(Color.Black)), _rect);
50 g.DrawLine(new Pen(new SolidBrush(lineColor)), _rect.Left + 2, _rect.Y + _rect.Height / 2, _rect.Right - 2, _rect.Y + _rect.Height / 2);
51 if (!item.IsExpansion)
52 {
53 g.DrawLine(new Pen(new SolidBrush(lineColor)), _rect.Left + _rect.Width / 2, _rect.Top + 2, _rect.Left + _rect.Width / 2, _rect.Bottom - 2);
54 }
55 }
56 }
控件的单击和双击时间来处理展开折叠事件
1 /// <summary>
2 /// 双击处理，主要用于检测节点双击展开折叠
3 /// </summary>
4 /// <param name="sender">The source of the event.</param>
5 /// <param name="e">The <see cref="EventArgs"/> instance containing the event data.</param>
6 void UCMindMapping_DoubleClick(object sender, EventArgs e)
7 {
8 var mouseLocation = this.PointToClient(Control.MousePosition);
9
10 bool bln = CheckExpansionDoubleClick(dataSource, mouseLocation);
11 if (bln)
12 {
13 ResetSize();
14 this.Parent.Refresh();
15 }
16 }
17
18 /// <summary>
19 /// 单击处理，主要用于单击节点事件和，展开关闭圆圈处理
20 /// </summary>
21 /// <param name="sender">The source of the event.</param>
22 /// <param name="e">The <see cref="EventArgs"/> instance containing the event data.</param>
23 void UCMindMapping_Click(object sender, EventArgs e)
24 {
25 var mouseLocation = this.PointToClient(Control.MousePosition);
26
27 bool bln = CheckExpansionClick(dataSource, mouseLocation);
28 if (bln)
29 {
30 ResetSize();
31 this.Parent.Refresh();
32 }
33 }
1 /// <summary>
2 /// 双击检查
3 /// </summary>
4 /// <param name="item">The item.</param>
5 /// <param name="mouseLocation">The mouse location.</param>
6 /// <returns><c>true</c> if XXXX, <c>false</c> otherwise.</returns>
7 private bool CheckExpansionDoubleClick(MindMappingItemEntity item, Point mouseLocation)
8 {
9 if (item == null)
10 return false;
11 else
12 {
13 if (item.DrawRectangle.Contains(mouseLocation))
14 {
15 item.IsExpansion = !item.IsExpansion;
16 return true;
17 }
18 if (item.Childrens != null && item.Childrens.Length > 0)
19 {
20 foreach (var child in item.Childrens)
21 {
22 var bln = CheckExpansionDoubleClick(child, mouseLocation);
23 if (bln)
24 return bln;
25 }
26 }
27 }
28 return false;
29 }
30
31 /// <summary>
32 /// 单击检查
33 /// </summary>
34 /// <param name="item">The item.</param>
35 /// <param name="mouseLocation">The mouse location.</param>
36 /// <returns><c>true</c> if XXXX, <c>false</c> otherwise.</returns>
37 private bool CheckExpansionClick(MindMappingItemEntity item, Point mouseLocation)
38 {
39 if (item == null)
40 return false;
41 else
42 {
43 if (ItemClicked != null && item.WorkingRectangle.Contains(mouseLocation))
44 {
45 ItemClicked(item, null);
46 }
47 else if (item.ExpansionRectangle.Contains(mouseLocation))
48 {
49 item.IsExpansion = !item.IsExpansion;
50 return true;
51 }
52 if (item.Childrens != null && item.Childrens.Length > 0)
53 {
54 foreach (var child in item.Childrens)
55 {
56 var bln = CheckExpansionClick(child, mouseLocation);
57 if (bln)
58 return bln;
59 }
60 }
61 }
62 return false;
63 }
完整代码
1 // ***********************************************************************
2 // Assembly : HZH_Controls
3 // Created : 2019-09-11
4 //
5 // ***********************************************************************
6 // <copyright file="UCMindMapping.cs">
7 // Copyright by Huang Zhenghui(黄正辉) All, QQ group:568015492 QQ:623128629 Email:623128629@qq.com
8 // </copyright>
9 //
10 // Blog: https://www.cnblogs.com/bfyx
11 // GitHub：https://github.com/kwwwvagaa/NetWinformControl
12 // gitee：https://gitee.com/kwwwvagaa/net_winform_custom_control.git
13 //
14 // If you use this code, please keep this note.
15 // ***********************************************************************
16 using System;
17 using System.Collections.Generic;
18 using System.Linq;
19 using System.Text;
20 using System.Windows.Forms;
21 using System.Drawing;
22 using System.Drawing.Drawing2D;
23 using System.ComponentModel;
24
25 namespace HZH_Controls.Controls
26 {
27 /// <summary>
28 /// Class UCMindMapping.
29 /// Implements the <see cref="System.Windows.Forms.UserControl" />
30 /// </summary>
31 /// <seealso cref="System.Windows.Forms.UserControl" />
32 internal class UCMindMapping : UserControl
33 {
34 /// <summary>
35 /// The line color
36 /// </summary>
37 private Color lineColor = Color.Black;
38
39 /// <summary>
40 /// Gets or sets the color of the line.
41 /// </summary>
42 /// <value>The color of the line.</value>
43 [Description("线条颜色"), Category("自定义")]
44 public Color LineColor
45 {
46 get { return lineColor; }
47 set
48 {
49 lineColor = value;
50 Refresh();
51 }
52 }
53 /// <summary>
54 /// The split width
55 /// </summary>
56 private int splitWidth = 50;
57 // private int itemHeight = 20;
58 /// <summary>
59 /// The padding
60 /// </summary>
61 private int padding = 20;
62
63 /// <summary>
64 /// The m rect working
65 /// </summary>
66 Rectangle m_rectWorking = Rectangle.Empty;
67 /// <summary>
68 /// Occurs when [item clicked].
69 /// </summary>
70 public event EventHandler ItemClicked;
71 /// <summary>
72 /// The data source
73 /// </summary>
74 private MindMappingItemEntity dataSource;
75 /// <summary>
76 /// Gets or sets the data source.
77 /// </summary>
78 /// <value>The data source.</value>
79 [Description("数据源"), Category("自定义")]
80 public MindMappingItemEntity DataSource
81 {
82 get { return dataSource; }
83 set
84 {
85 dataSource = value;
86
87 ResetSize();
88 }
89 }
90 /// <summary>
91 /// Initializes a new instance of the <see cref="UCMindMapping"/> class.
92 /// </summary>
93 public UCMindMapping()
94 {
95 this.SetStyle(ControlStyles.AllPaintingInWmPaint, true);
96 this.SetStyle(ControlStyles.DoubleBuffer, true);
97 this.SetStyle(ControlStyles.ResizeRedraw, true);
98 this.SetStyle(ControlStyles.Selectable, true);
99 this.SetStyle(ControlStyles.SupportsTransparentBackColor, true);
100 this.SetStyle(ControlStyles.UserPaint, true);
101 this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.None;
102 this.Click += UCMindMapping_Click;
103 this.DoubleClick += UCMindMapping_DoubleClick;
104 this.Load += UCMindMapping_Load;
105 }
106
107 /// <summary>
108 /// Handles the Load event of the UCMindMapping control.
109 /// </summary>
110 /// <param name="sender">The source of the event.</param>
111 /// <param name="e">The <see cref="EventArgs"/> instance containing the event data.</param>
112 void UCMindMapping_Load(object sender, EventArgs e)
113 {
114 if (this.Parent != null)
115 {
116 //父控件大小改变时重置大小和位置
117 this.Parent.SizeChanged += (a, b) =>
118 {
119 ResetSize();
120 };
121 }
122 }
123
124 /// <summary>
125 /// 双击处理，主要用于检测节点双击展开折叠
126 /// </summary>
127 /// <param name="sender">The source of the event.</param>
128 /// <param name="e">The <see cref="EventArgs"/> instance containing the event data.</param>
129 void UCMindMapping_DoubleClick(object sender, EventArgs e)
130 {
131 var mouseLocation = this.PointToClient(Control.MousePosition);
132
133 bool bln = CheckExpansionDoubleClick(dataSource, mouseLocation);
134 if (bln)
135 {
136 ResetSize();
137 this.Parent.Refresh();
138 }
139 }
140
141 /// <summary>
142 /// 单击处理，主要用于单击节点事件和，展开关闭圆圈处理
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 UCMindMapping_Click(object sender, EventArgs e)
147 {
148 var mouseLocation = this.PointToClient(Control.MousePosition);
149
150 bool bln = CheckExpansionClick(dataSource, mouseLocation);
151 if (bln)
152 {
153 ResetSize();
154 this.Parent.Refresh();
155 }
156 }
157
158 /// <summary>
159 /// 双击检查
160 /// </summary>
161 /// <param name="item">The item.</param>
162 /// <param name="mouseLocation">The mouse location.</param>
163 /// <returns><c>true</c> if XXXX, <c>false</c> otherwise.</returns>
164 private bool CheckExpansionDoubleClick(MindMappingItemEntity item, Point mouseLocation)
165 {
166 if (item == null)
167 return false;
168 else
169 {
170 if (item.DrawRectangle.Contains(mouseLocation))
171 {
172 item.IsExpansion = !item.IsExpansion;
173 return true;
174 }
175 if (item.Childrens != null && item.Childrens.Length > 0)
176 {
177 foreach (var child in item.Childrens)
178 {
179 var bln = CheckExpansionDoubleClick(child, mouseLocation);
180 if (bln)
181 return bln;
182 }
183 }
184 }
185 return false;
186 }
187
188 /// <summary>
189 /// 单击检查
190 /// </summary>
191 /// <param name="item">The item.</param>
192 /// <param name="mouseLocation">The mouse location.</param>
193 /// <returns><c>true</c> if XXXX, <c>false</c> otherwise.</returns>
194 private bool CheckExpansionClick(MindMappingItemEntity item, Point mouseLocation)
195 {
196 if (item == null)
197 return false;
198 else
199 {
200 if (ItemClicked != null && item.WorkingRectangle.Contains(mouseLocation))
201 {
202 ItemClicked(item, null);
203 }
204 else if (item.ExpansionRectangle.Contains(mouseLocation))
205 {
206 item.IsExpansion = !item.IsExpansion;
207 return true;
208 }
209 if (item.Childrens != null && item.Childrens.Length > 0)
210 {
211 foreach (var child in item.Childrens)
212 {
213 var bln = CheckExpansionClick(child, mouseLocation);
214 if (bln)
215 return bln;
216 }
217 }
218 }
219 return false;
220 }
221
222 /// <summary>
223 /// 引发 <see cref="E:System.Windows.Forms.Control.Paint" /> 事件。
224 /// </summary>
225 /// <param name="e">包含事件数据的 <see cref="T:System.Windows.Forms.PaintEventArgs" />。</param>
226 protected override void OnPaint(PaintEventArgs e)
227 {
228 try
229 {
230 base.OnPaint(e);
231 if (m_rectWorking == Rectangle.Empty || m_rectWorking == null)
232 return;
233 var g = e.Graphics;
234 g.SetGDIHigh();
235
236 int intHeight = dataSource.AllChildrensMaxShowHeight;
237 dataSource.WorkingRectangle = new RectangleF(m_rectWorking.Left, m_rectWorking.Top + (m_rectWorking.Height - intHeight) / 2, m_rectWorking.Width, intHeight);
238
239 DrawItem(dataSource, g);
240 }
241 catch (Exception exc)
242 {
243 MessageBox.Show(exc.ToString(), "错误");
244 }
245 }
246
247 /// <summary>
248 /// 画节点
249 /// </summary>
250 /// <param name="item">The item.</param>
251 /// <param name="g">The g.</param>
252 private void DrawItem(MindMappingItemEntity item, Graphics g)
253 {
254 //节点
255 var size = g.MeasureString(item.Text, item.Font);
256 item.DrawRectangle = new RectangleF(item.WorkingRectangle.Left + 2, item.WorkingRectangle.Top + (item.WorkingRectangle.Height - size.Height) / 2 + 2, size.Width + 4, size.Height + 4);
257 GraphicsPath drawPath = item.DrawRectangle.CreateRoundedRectanglePath(5);
258 g.FillPath(new SolidBrush(item.BackColor), drawPath);
259 g.DrawString(item.Text, item.Font, new SolidBrush(item.ForeColor), item.DrawRectangle.Location.X + 2, item.DrawRectangle.Location.Y + 2);
260 //子节点
261 if (item.Childrens != null && item.IsExpansion)
262 {
263 for (int i = 0; i < item.Childrens.Length; i++)
264 {
265 var child = item.Childrens[i];
266 if (i == 0)
267 {
268 child.WorkingRectangle = new RectangleF(item.DrawRectangle.Right + splitWidth, item.WorkingRectangle.Top, item.WorkingRectangle.Width - (item.DrawRectangle.Width + splitWidth), child.AllChildrensMaxShowHeight);
269 }
270 else
271 {
272 child.WorkingRectangle = new RectangleF(item.DrawRectangle.Right + splitWidth, item.Childrens[i - 1].WorkingRectangle.Bottom, item.WorkingRectangle.Width - (item.DrawRectangle.Width + splitWidth), child.AllChildrensMaxShowHeight);
273 }
274 DrawItem(child, g);
275 }
276 }
277 //连线
278 if (item.ParentItem != null)
279 {
280 g.DrawLines(new Pen(new SolidBrush(lineColor), 1), new PointF[]
281 {
282 new PointF(item.ParentItem.DrawRectangle.Right,item.ParentItem.DrawRectangle.Top+item.ParentItem.DrawRectangle.Height/2),
283 new PointF(item.ParentItem.DrawRectangle.Right+12,item.ParentItem.DrawRectangle.Top+item.ParentItem.DrawRectangle.Height/2),
284 //new PointF(item.ParentItem.DrawRectangle.Right+12,item.DrawRectangle.Top+item.DrawRectangle.Height/2),
285 new PointF(item.DrawRectangle.Left-12,item.DrawRectangle.Top+item.DrawRectangle.Height/2),
286 new PointF(item.DrawRectangle.Left,item.DrawRectangle.Top+item.DrawRectangle.Height/2),
287 });
288 }
289 //展开折叠按钮
290 if (item.Childrens != null && item.Childrens.Length > 0)
291 {
292 RectangleF _rect = new RectangleF(item.DrawRectangle.Right + 1, item.DrawRectangle.Top + (item.DrawRectangle.Height - 10) / 2, 10, 10);
293 item.ExpansionRectangle = _rect;
294 g.FillEllipse(new SolidBrush(this.BackColor), _rect);
295 g.DrawEllipse(new Pen(new SolidBrush(Color.Black)), _rect);
296 g.DrawLine(new Pen(new SolidBrush(lineColor)), _rect.Left + 2, _rect.Y + _rect.Height / 2, _rect.Right - 2, _rect.Y + _rect.Height / 2);
297 if (!item.IsExpansion)
298 {
299 g.DrawLine(new Pen(new SolidBrush(lineColor)), _rect.Left + _rect.Width / 2, _rect.Top + 2, _rect.Left + _rect.Width / 2, _rect.Bottom - 2);
300 }
301 }
302 }
303
304
305 /// <summary>
306 /// 重置大小
307 /// </summary>
308 private void ResetSize()
309 {
310 if (this.Parent == null)
311 return;
312 try
313 {
314 ControlHelper.FreezeControl(this, true);
315 if (dataSource == null)
316 {
317 m_rectWorking = Rectangle.Empty;
318 this.Size = this.Parent.Size;
319 }
320 else
321 {
322 int intWidth = dataSource.AllChildrensMaxShowWidth;
323 int intHeight = dataSource.AllChildrensMaxShowHeight;
324 this.Width = intWidth + padding * 2;
325 this.Height = intHeight + padding * 2;
326 if (this.Width < this.Parent.Width)
327 this.Width = this.Parent.Width;
328 m_rectWorking = new Rectangle(padding, padding, intWidth, intHeight);
329 if (this.Height > this.Parent.Height)
330 {
331 //this.Location = new Point(0, 0);
332 }
333 else
334 this.Location = new Point(0, (this.Parent.Height - this.Height) / 2);
335 }
336 }
337 finally
338 {
339 ControlHelper.FreezeControl(this, false);
340 }
341 }
342 }
343 }
最后再添加一个父控件，来包裹该控件，用以可以有滚动条的处理
添加一个用户控件UCMindMappingPanel，控件上添加一个上面新增的ucMindMapping，
完整代码
1 // ***********************************************************************
2 // Assembly : HZH_Controls
3 // Created : 2019-09-11
4 //
5 // ***********************************************************************
6 // <copyright file="UCMindMappingPanel.cs">
7 // Copyright by Huang Zhenghui(黄正辉) All, QQ group:568015492 QQ:623128629 Email:623128629@qq.com
8 // </copyright>
9 //
10 // Blog: https://www.cnblogs.com/bfyx
11 // GitHub：https://github.com/kwwwvagaa/NetWinformControl
12 // gitee：https://gitee.com/kwwwvagaa/net_winform_custom_control.git
13 //
14 // If you use this code, please keep this note.
15 // ***********************************************************************
16 using System;
17 using System.Collections.Generic;
18 using System.ComponentModel;
19 using System.Drawing;
20 using System.Data;
21 using System.Linq;
22 using System.Text;
23 using System.Windows.Forms;
24
25 namespace HZH_Controls.Controls
26 {
27 /// <summary>
28 /// Class UCMindMappingPanel.
29 /// Implements the <see cref="System.Windows.Forms.UserControl" />
30 /// </summary>
31 /// <seealso cref="System.Windows.Forms.UserControl" />
32 public partial class UCMindMappingPanel : UserControl
33 {
34 /// <summary>
35 /// The data source
36 /// </summary>
37 private MindMappingItemEntity dataSource;
38
39 /// <summary>
40 /// Gets or sets the data source.
41 /// </summary>
42 /// <value>The data source.</value>
43 [Description("数据源"), Category("自定义")]
44 public MindMappingItemEntity DataSource
45 {
46 get { return dataSource; }
47 set
48 {
49 dataSource = value;
50 this.ucMindMapping1.DataSource = value;
51 }
52 }
53 /// <summary>
54 /// Gets or sets the data source.
55 /// </summary>
56 /// <value>The data source.</value>
57 [Description("数据源"), Category("自定义")]
58 public event EventHandler ItemClicked;
59
60 /// <summary>
61 /// The line color
62 /// </summary>
63 private Color lineColor = Color.Black;
64
65 /// <summary>
66 /// Gets or sets the color of the line.
67 /// </summary>
68 /// <value>The color of the line.</value>
69 [Description("线条颜色"), Category("自定义")]
70 public Color LineColor
71 {
72 get { return lineColor; }
73 set
74 {
75 lineColor = value;
76 this.ucMindMapping1.LineColor = value;
77 }
78 }
79 /// <summary>
80 /// Initializes a new instance of the <see cref="UCMindMappingPanel"/> class.
81 /// </summary>
82 public UCMindMappingPanel()
83 {
84 this.SetStyle(ControlStyles.AllPaintingInWmPaint, true);
85 this.SetStyle(ControlStyles.DoubleBuffer, true);
86 this.SetStyle(ControlStyles.ResizeRedraw, true);
87 this.SetStyle(ControlStyles.Selectable, true);
88 this.SetStyle(ControlStyles.SupportsTransparentBackColor, true);
89 this.SetStyle(ControlStyles.UserPaint, true);
90 InitializeComponent();
91 ucMindMapping1.ItemClicked += ucMindMapping1_ItemClicked;
92 }
93
94 void ucMindMapping1_ItemClicked(object sender, EventArgs e)
95 {
96 if (ItemClicked != null)
97 {
98 ItemClicked(sender, e);
99 }
100 }
101 }
102 }
1 namespace HZH_Controls.Controls
2 {
3 partial class UCMindMappingPanel
4 {
5 /// <summary>
6 /// 必需的设计器变量。
7 /// </summary>
8 private System.ComponentModel.IContainer components = null;
9
10 /// <summary>
11 /// 清理所有正在使用的资源。
12 /// </summary>
13 /// <param name="disposing">如果应释放托管资源，为 true；否则为 false。</param>
14 protected override void Dispose(bool disposing)
15 {
16 if (disposing && (components != null))
17 {
18 components.Dispose();
19 }
20 base.Dispose(disposing);
21 }
22
23 #region 组件设计器生成的代码
24
25 /// <summary>
26 /// 设计器支持所需的方法 - 不要
27 /// 使用代码编辑器修改此方法的内容。
28 /// </summary>
29 private void InitializeComponent()
30 {
31 this.ucMindMapping1 = new HZH_Controls.Controls.UCMindMapping();
32 this.SuspendLayout();
33 //
34 // ucMindMapping1
35 //
36 this.ucMindMapping1.Location = new System.Drawing.Point(0, 0);
37 this.ucMindMapping1.Name = "ucMindMapping1";
38 this.ucMindMapping1.Size = new System.Drawing.Size(200, 200);
39 this.ucMindMapping1.TabIndex = 0;
40 //
41 // UCMindMappingPanel
42 //
43 this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.None;
44 this.AutoScroll = true;
45 this.BackColor = System.Drawing.Color.White;
46 this.Controls.Add(this.ucMindMapping1);
47 this.Name = "UCMindMappingPanel";
48 this.Size = new System.Drawing.Size(200, 200);
49 this.ResumeLayout(false);
50
51 }
52
53 #endregion
54
55 private UCMindMapping ucMindMapping1;
56 }
57 }
最后的话
如果你喜欢的话，请到 https://gitee.com/kwwwvagaa/net_winform_custom_control 点个星星吧
来源：https://www.cnblogs.com/bfyx/p/11506080.html