Metis_xctg/Core/CustomControl/UCTrackBar.cs

using System;
using System.Windows.Forms;
using System.Drawing;
using System.ComponentModel;

namespace PaintDotNet.CustomControl
{
    public partial class UCTrackBar : Control
    {
        [Description("Left值改变事件"), Category("自定义")]
        public event EventHandler Value1Changed;
        [Description("Center值改变事件"), Category("自定义")]
        public event EventHandler Value2Changed;
        [Description("Right值改变事件"), Category("自定义")]
        public event EventHandler Value3Changed;

        [Description("鼠标抬起事件"), Category("自定义")]
        public event EventHandler ValueMouseUp;

        private int dcimalDigits = 0;

        [Description("值小数精确位数"), Category("自定义")]
        public int DcimalDigits
        {
            get { return dcimalDigits; }
            set { dcimalDigits = value; }
        }

        private float lineWidth = 10;

        [Description("线宽度"), Category("自定义")]
        public float LineWidth
        {
            get { return lineWidth; }
            set { lineWidth = value; }
        }

        private float minValue = 0;

        [Description("最小值"), Category("自定义")]
        public float MinValue
        {
            get { return minValue; }
            set
            {
                if (minValue > m1_value)
                    return;
                if (minValue > m2_value)
                    return;
                if (minValue > m3_value)
                    return;
                minValue = value;
                this.Refresh();
            }
        }

        private float maxValue = 255;//256;

        [Description("最大值"), Category("自定义")]
        public float MaxValue
        {
            get { return maxValue; }
            set
            {
                if (value < m1_value)
                    return;
                if (value < m2_value)
                    return;
                if (value < m3_value)
                    return;
                maxValue = value;
                this.Refresh();
            }
        }

        private float m1_value = 0;//2;//0;
        private float m2_value = 127;//128;
        private float m3_value = 255;//254;//256;

        [Description("Left值"), Category("自定义")]
        public float Value1
        {
            get { return this.m1_value; }
            set
            {
                if (value > maxValue || value < minValue)
                    return;
                var v = (float)Math.Round((double)value, dcimalDigits);
                if (this.m1_value == v)
                    return;
                this.m1_value = v;
            }
        }

        [Description("Center值"), Category("自定义")]
        public float Value2
        {
            get { return this.m2_value; }
            set
            {
                if (value > maxValue || value < minValue)
                    return;
                var v = (float)Math.Round((double)value, dcimalDigits);
                if (this.m2_value == v)
                    return;
                this.m2_value = v;
                //this.Refresh();
                //if (Value2Changed != null)
                //{
                //    Value2Changed(this, null);
                //}
            }
        }

        [Description("Right值"), Category("自定义")]
        public float Value3
        {
            get { return this.m3_value; }
            set
            {
                if (value > maxValue || value < minValue)
                    return;
                var v = (float)Math.Round((double)value, dcimalDigits);
                if (this.m3_value == v)
                    return;
                this.m3_value = v;
                //this.Refresh();
                //if (Value3Changed != null)
                //{
                //    Value3Changed(this, null);
                //}
            }
        }

        private Color m_lineColor = Color.FromArgb(255, 77, 59);

        [Description("线颜色"), Category("自定义")]
        public Color LineColor
        {
            get { return m_lineColor; }
            set
            {
                m_lineColor = value;
                this.Refresh();
            }
        }
        RectangleF m_lineRectangle;
        RectangleF m1_trackRectangle;
        RectangleF m2_trackRectangle;
        RectangleF m3_trackRectangle;

        public UCTrackBar()
        {
            this.Size = new Size(250, 30);
            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.MouseDown += UCTrackBar_MouseDown;
            this.MouseMove += UCTrackBar_MouseMove;
            this.MouseUp += UCTrackBar_MouseUp;
        }

        bool bln1Down = false;
        bool bln2Down = false;
        bool bln3Down = false;
        void UCTrackBar_MouseDown(object sender, MouseEventArgs e)
        {
            float locationValue = ((float)e.Location.X / (float)this.Width) * (maxValue - minValue);
            if (Math.Abs(locationValue - m3_value) < 2 || Math.Abs(locationValue - m2_value) < 2 || Math.Abs(locationValue - m1_value) < 2 ||/*m_lineRectangle.Contains(e.Location) ||*/ m1_trackRectangle.Contains(e.Location) || m2_trackRectangle.Contains(e.Location) || m3_trackRectangle.Contains(e.Location))
            {
                float minValue = Math.Min(Math.Abs(locationValue - m3_value), Math.Min(Math.Abs(locationValue - m2_value), Math.Abs(locationValue - m1_value)));
                if (Math.Abs(locationValue - m3_value) == minValue)
                {
                    bln3Down = true;
                    bln2Down = false;
                    bln1Down = false;
                }
                //Value = ((float)e.Location.X / (float)this.Width) * (maxValue - minValue);
                else if (Math.Abs(locationValue - m2_value) == minValue)
                {
                    bln2Down = true;
                    bln3Down = false;
                    bln1Down = false;
                }
                else if (Math.Abs(locationValue - m1_value) == minValue)
                {
                    bln1Down = true;
                    bln2Down = false;
                    bln3Down = false;
                }
            }
        }
        void UCTrackBar_MouseMove(object sender, MouseEventArgs e)
        {
            if (bln1Down)
            {
                float value = ((float)e.Location.X / (float)this.Width) * (maxValue - minValue);
                if (value > maxValue || value < minValue)
                    return;
                Value1 = Math.Min(value, Value2 - 1);
                this.Refresh();
                if (Value1Changed != null)
                {
                    Value1Changed(this, null);
                }
            }
            if (bln2Down)
            {
                float value = ((float)e.Location.X / (float)this.Width) * (maxValue - minValue);
                if (value > maxValue || value < minValue)
                    return;
                Value2 = Math.Max(Value1 + 1, Math.Min(value, Value3 - 1));
                this.Refresh();
                if (Value2Changed != null)
                {
                    Value2Changed(this, null);
                }
            }
            if (bln3Down)
            {
                float value = ((float)e.Location.X / (float)this.Width) * (maxValue - minValue);
                if (value > maxValue || value < minValue)
                    return;
                Value3 = Math.Max(value, Value2 + 1);
                this.Refresh();
                if (Value3Changed != null)
                {
                    Value3Changed(this, null);
                }
            }
        }
        void UCTrackBar_MouseUp(object sender, MouseEventArgs e)
        {
            bln1Down = false;
            bln2Down = false;
            bln3Down = false;

            if (ValueMouseUp != null)
            {
                ValueMouseUp(this, null);
            }
        }


        protected override void OnPaint(PaintEventArgs e)
        {
            base.OnPaint(e);
            Graphics g = e.Graphics;
            //g.SetGDIHigh();
            m_lineRectangle = new RectangleF(lineWidth, (this.Size.Height - lineWidth) / 2, this.Size.Width - lineWidth * 2, lineWidth);
            ////GraphicsPath pathLine = ControlHelper.CreateRoundedRectanglePath(m_lineRectangle, 5);
            ////g.FillPath(new SolidBrush(m_lineColor), pathLine);
            //m_trackRectangle = new RectangleF(m_lineRectangle.Left - lineWidth + (((float)m_value / (float)(maxValue - minValue)) * (this.Size.Width - lineWidth * 2)), (this.Size.Height - lineWidth * 2) / 2, lineWidth * 2 - 4, lineWidth * 2 - 4);
            m1_trackRectangle = new RectangleF(m_lineRectangle.Left - lineWidth + (((float)m1_value / (float)(maxValue - minValue)) * (this.Size.Width - lineWidth * 2)), (this.Size.Height - lineWidth * 2) / 2, lineWidth * 2 - 4, lineWidth * 2 - 4);
            m2_trackRectangle = new RectangleF(m_lineRectangle.Left - lineWidth + (((float)m2_value / (float)(maxValue - minValue)) * (this.Size.Width - lineWidth * 2)), (this.Size.Height - lineWidth * 2) / 2, lineWidth * 2 - 4, lineWidth * 2 - 4);
            m3_trackRectangle = new RectangleF(m_lineRectangle.Left - lineWidth + (((float)m3_value / (float)(maxValue - minValue)) * (this.Size.Width - lineWidth * 2)), (this.Size.Height - lineWidth * 2) / 2, lineWidth * 2 - 4, lineWidth * 2 - 4);
            ////m_trackRectangle -= 4;
            //g.FillEllipse(new SolidBrush(m_lineColor), m1_trackRectangle);
            //g.FillEllipse(new SolidBrush(m_lineColor), m2_trackRectangle);
            //g.FillEllipse(new SolidBrush(m_lineColor), m3_trackRectangle);
            //g.FillEllipse(Brushes.White, new RectangleF(m1_trackRectangle.X + m1_trackRectangle.Width / 4, m1_trackRectangle.Y + m1_trackRectangle.Height / 4, m1_trackRectangle.Width / 2, m1_trackRectangle.Height / 2));
            //g.FillEllipse(Brushes.White, new RectangleF(m2_trackRectangle.X + m2_trackRectangle.Width / 4, m2_trackRectangle.Y + m2_trackRectangle.Height / 4, m2_trackRectangle.Width / 2, m2_trackRectangle.Height / 2));
            //g.FillEllipse(Brushes.White, new RectangleF(m3_trackRectangle.X + m3_trackRectangle.Width / 4, m3_trackRectangle.Y + m3_trackRectangle.Height / 4, m3_trackRectangle.Width / 2, m3_trackRectangle.Height / 2));

            Brush brush = Brushes.Black;
            //Pen pen = (Pen)Pens.Gray.Clone();

            //g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.AntiAlias;

            int triangleHalfLength = 7;// 3 * 2;
            int triangleSize = 13;

            int pos1 = triangleHalfLength + (int)(m_lineRectangle.Left - lineWidth + (((float)m1_value / (float)(maxValue - minValue)) * (this.Size.Width - lineWidth * 2)));
            int pos2 = triangleHalfLength + (int)(m_lineRectangle.Left - lineWidth + (((float)m2_value / (float)(maxValue - minValue)) * (this.Size.Width - lineWidth * 2)));
            int pos3 = triangleHalfLength + (int)(m_lineRectangle.Left - lineWidth + (((float)m3_value / (float)(maxValue - minValue)) * (this.Size.Width - lineWidth * 2)));
            
            Point a1 = new Point(pos1 - triangleHalfLength, triangleSize - 1);
            Point b1 = new Point(pos1, 0);
            Point c1 = new Point(pos1 + triangleHalfLength, triangleSize - 1);

            //Point a2 = new Point(a1.X, Height - 1 - a1.Y);
            //Point b2 = new Point(b1.X, Height - 1 - b1.Y);
            //Point c2 = new Point(c1.X, Height - 1 - c1.Y);
            Point a2 = new Point(pos2 - triangleHalfLength, triangleSize - 1);
            Point b2 = new Point(pos2, 0);
            Point c2 = new Point(pos2 + triangleHalfLength, triangleSize - 1);
            Point a3 = new Point(pos3 - triangleHalfLength, triangleSize - 1);
            Point b3 = new Point(pos3, 0);
            Point c3 = new Point(pos3 + triangleHalfLength, triangleSize - 1);

            g.FillPolygon(brush, new Point[] { a1, b1, c1, a1 });
            g.FillPolygon(brush, new Point[] { a2, b2, c2, a2 });
            g.FillPolygon(brush, new Point[] { a3, b3, c3, a3 });
            //if (this.drawNearNub)
            //{
            //    g.FillPolygon(brush, new Point[] { a1, b1, c1, a1 });
            //}

            //if (this.drawFarNub)
            //{
            //    g.FillPolygon(brush, new Point[] { a2, b2, c2, a2 });
            //}
        }
    }
}
//原文链接：https://blog.csdn.net/kwwwvagaa/article/details/100622682