找不到类型或命名空间名称“GraphicsPath”(是否缺少 using 指令或程序集引用?)

Question

找不到类型或命名空间名称“GraphicsPath”(是否缺少 using 指令或程序集引用?)using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Data;
using System.Text;
using System.Windows.Forms;
namespace hstwintoolbox
{
    public partial class hstbutton : Button
    {
        public hstbutton()
        {
            InitializeComponent();            BackColor = Color.YellowGreen;            m_Region = CreateRoundRectangle(this.ClientRectangle, m_radius);
            if (m_Region != null)
                this.Region = new Region(m_Region);            this.SetStyle(ControlStyles.AllPaintingInWmPaint |
                ControlStyles.DoubleBuffer |
                ControlStyles.UserPaint, true);
        }
        private GraphicsPath m_Region = null;        private bool IsMouseHover = false;        private bool IsMouseDown = false;        private int m_radius = 3;        private Color m_outBorderColor = Color.DarkGreen;        private Color m_upperShineColor = Color.White;        private Color m_bottomShineColor = Color.FromArgb(140, Color.White);
        public int ButtonCornorRadius
        {
            get
            {
                return m_radius;
            }
            set
            {
                if (value < 0)
                    return;
                else
                    m_radius = value;
            }
        }        public Color OutBorderColor
        {
            get
            {
                return m_outBorderColor;
            }
            set
            {
                m_outBorderColor = value;
            }
        }        public Color UpperShineColor
        {
            get
            {
                return m_upperShineColor;
            }
            set
            {
                m_upperShineColor = value;
            }
        }        public Color BottomShineColor
        {
            get
            {
                return m_bottomShineColor;
            }
            set
            {
                m_bottomShineColor = value;
            }
        }
        protected virtual GraphicsPath CreateRoundRectangle(Rectangle rectangle, int radius)
        {
            GraphicsPath path = new GraphicsPath();
            int l = rectangle.Left;
            int t = rectangle.Top;
            int w = rectangle.Width;
            int h = rectangle.Height;
            int d = radius << 1;
            path.AddArc(l, t, d, d, 180, 90); // topleft
            path.AddLine(l + radius, t, l + w - radius, t); // top
            path.AddArc(l + w - d, t, d, d, 270, 90); // topright
            path.AddLine(l + w, t + radius, l + w, t + h - radius); // right
            path.AddArc(l + w - d, t + h - d, d, d, 0, 90); // bottomright
            path.AddLine(l + w - radius, t + h, l + radius, t + h); // bottom
            path.AddArc(l, t + h - d, d, d, 90, 90); // bottomleft
            path.AddLine(l, t + h - radius, l, t + radius); // left
            path.CloseFigure();
            return path;
        }        protected override void OnMouseDown(MouseEventArgs mevent)
        {
            IsMouseDown = true;
            this.Invalidate();
            base.OnMouseDown(mevent);
        }        protected override void OnMouseUp(MouseEventArgs mevent)
        {
            IsMouseDown = false;
            this.Invalidate();
            base.OnMouseUp(mevent);
        }        protected override void OnMouseEnter(EventArgs e)
        {
            IsMouseHover = true;
            this.Invalidate();
            base.OnMouseEnter(e);
        }        protected override void OnMouseLeave(EventArgs e)
        {
            base.OnMouseLeave(e);
            IsMouseHover = false;
            this.Invalidate();
        }        protected override void OnGotFocus(EventArgs e)
        {
            IsMouseHover = true;
            this.Invalidate();
            base.OnGotFocus(e);
        }        protected override void OnLostFocus(EventArgs e)
        {
            base.OnLostFocus(e);
            IsMouseHover = false;
            this.Invalidate();
        }        protected override void OnSizeChanged(EventArgs e)
        {
            m_Region = CreateRoundRectangle(this.ClientRectangle, m_radius);
            if (m_Region != null)
                this.Region = this.Region = new Region(m_Region);            base.OnSizeChanged(e);
        }
        protected virtual void DrawBorder(Graphics g, Pen pen)
        {
            if (m_Region != null)
            {
                g.SmoothingMode = SmoothingMode.HighQuality;
                g.InterpolationMode = InterpolationMode.HighQualityBilinear;                g.DrawPath(pen, CreateRoundRectangle(new Rectangle(this.ClientRectangle.Left, this.ClientRectangle.Top, this.ClientRectangle.Width - 1, this.ClientRectangle.Height - 1), m_radius));                g.SmoothingMode = SmoothingMode.Default;
                g.InterpolationMode = InterpolationMode.Default;
            }            pen.Dispose();
            pen = null;
        }        protected virtual void DrawUpperShine(Graphics g)
        {
            Color c1 = Color.FromArgb(200, this.m_upperShineColor);
            Color c2 = Color.FromArgb(100, Color.White);            Rectangle rc = new Rectangle(this.ClientRectangle.Left, this.ClientRectangle.Top, Width - 1, Height / 2);
            if(IsMouseDown)
                rc = new Rectangle(this.ClientRectangle.Left, this.ClientRectangle.Top, Width - 1, (Height-10) / 2);            using (LinearGradientBrush lbrush = new LinearGradientBrush(rc, c1, c2,
                LinearGradientMode.Vertical))
            {
                g.FillRectangle(lbrush, rc);
            }
        }        protected virtual void DrawBottomShine(Graphics g)
        {
            Rectangle rc1 = new Rectangle(this.ClientRectangle.Left,
                this.ClientRectangle.Top + this.ClientRectangle.Height / 2,
                this.ClientRectangle.Width / 2, this.ClientRectangle.Height / 2);            Rectangle rc2 = new Rectangle(this.ClientRectangle.Left + this.ClientRectangle.Width / 2,
                this.ClientRectangle.Top + this.ClientRectangle.Height / 2,
                this.ClientRectangle.Width / 2, this.ClientRectangle.Height / 2);            Color c1 = BackColor;
            Color c2 = m_bottomShineColor;            using (LinearGradientBrush lbrush = new LinearGradientBrush(rc1, c1, c2,
                LinearGradientMode.ForwardDiagonal))
            {
                g.FillRectangle(lbrush, rc1);
            }            using (LinearGradientBrush lbrush = new LinearGradientBrush(rc2, c1, c2,
                LinearGradientMode.BackwardDiagonal))
            {
                g.FillRectangle(lbrush, rc2);
            }
        }        protected virtual void DrawDisable(Graphics g,Brush brush,Pen pen)
        {
            g.FillPath(brush, m_Region);            DrawBorder(g, pen);            brush.Dispose();
            pen.Dispose();
            brush = null;
            pen = null;
        }        protected virtual void DrawString(Graphics g)
        {
            if (this.Text.Trim() == "")
                return;            int x = 0, y = 0;
            int w = 0, h = 0;
            Size sz = g.MeasureString(Text, Font).ToSize();            w = sz.Width > Width ? Width : sz.Width;
            h = sz.Height > Height ? Height : sz.Height;            switch (TextAlign)
            {
                case ContentAlignment.MiddleCenter:
                    {
                        x = sz.Width > Width ? 0 : (Width - sz.Width) / 2;
                        y = sz.Height > Height ? 0 : (Height - sz.Height) / 2;
                    }
                    break;                case ContentAlignment.MiddleLeft:
                    {
                        x = 2;
                        y = sz.Height > Height ? 0 : (Height - sz.Height) / 2;
                    } break;                case ContentAlignment.MiddleRight:
                    {
                        x = sz.Width > sz.Width ? 0 : (Width - sz.Width) - 2;
                        y = sz.Height > Height ? 0 : (Height - sz.Height) / 2;
                    } break;                default:
                    {
                        //the other tyles in middle center.
                        x = sz.Width > Width ? 0 : (Width - sz.Width) / 2;
                        y = sz.Height > Height ? 0 : (Height - sz.Height) / 2;
                    } break;
            }            Pen pen = new Pen(ForeColor);
            if (!Enabled)
                pen = new Pen(Color.Gray);            g.DrawString(Text, Font, pen.Brush, new RectangleF(
                (float)x, (float)y, (float)w+3, (float)h));            pen.Dispose();
            pen = null;
        }        protected override void OnPaint(PaintEventArgs pevent)
        {
            Pen pen = new Pen(m_outBorderColor);
            Brush brush = new SolidBrush(BackColor);            if (!this.Enabled)
            {
                DrawDisable(pevent.Graphics, brush, pen);
                DrawString(pevent.Graphics);
                return;
            }            pevent.Graphics.FillPath(brush, m_Region);            DrawUpperShine(pevent.Graphics);            if(IsMouseHover)
                DrawBottomShine(pevent.Graphics);            DrawString(pevent.Graphics);            DrawBorder(pevent.Graphics, pen);
            //base.OnPaint(pevent);
        }
    }
}

Answer 1

http://msdn.microsoft.com/zh-cn/library/system.drawing.drawing2d.graphicspath.aspx确定引用中System.Drawing.dll,是否已经添加

Answer 2

学会自己找类型的定义：比如：
GraphicsPath”(是否缺少 using 指令或程序集引用?)
打开对象浏览器，输入GraphicsPath，查找，，看结果吧！

Answer 3

using System.Drawing; 
using System.Drawing.Drawing2D; 
using System.Drawing.Imaging; 

Answer 4

GraphicsPath 类 
命名空间:System.Drawing.Drawing2D
程序集:System.Drawing（在 system.drawing.dll 中）