signaturebox.cs

采用vc#.net和sqlce实现智能手机端和服务器数据交换

using System;
using System.Collections;
using System.Drawing;
using System.Windows.Forms;

namespace Microsoft.Sql.SqlCe.Samples.Cs.IBuySpyDelivery.IBuySpyDevice
{

    /// <summary>
    /// This class captures and displays the signature.
    /// </summary>
    public class SignatureBox : Control 
    {

        int               numPoints  = 0;
        Pen               pen        = null;
        Stroke            stroke     = null;
        ArrayList         signature  = null;
        SolidBrush        brush      = null;
        int               penWidth   = 2;
        
        private Graphics  graphics;
        private Bitmap    bitmap;
        private bool      hasCapture;
        private int       oldX, oldY;
        private int       maxWidth, maxHeight;

        public short[] Signature 
        {
            get 
            {
                int index = 0;
                short[] buf = new short[numPoints];

                for (int i=0; i<signature.Count; i++) 
                {
                    short[] stroke = null;
                    stroke = ((Stroke)signature[i]).ToShortArray(); 
                    Array.Copy(stroke, 0, buf, index, stroke.Length);
                    index += stroke.Length;
                }

                return buf;
            }

            set 
            {
                numPoints = 0;
                signature.Clear();

                int prevIndx = 0;
                for (int i=0; i < value.Length; i += 2) 
                {
                    if ( unchecked ((short) 0xFFFF) == value[i]) 
                    {
                        Stroke stroke = new Stroke(50);
                        stroke.Fill(value, prevIndx, i);
                        signature.Add(stroke);
                        prevIndx = i + 2;
                    }
                }
                
                numPoints = value.Length;
            }
        }

        public int PenWidth
        {
            set
            {
                penWidth = value;
            }
        }

        public SignatureBox (int width, int length) 
        {
            this.maxHeight = length;
            this.maxWidth = width;

            this.bitmap = new Bitmap(this.maxWidth, this.maxHeight);
            this.graphics = Graphics.FromImage(this.bitmap);
            this.graphics.FillRectangle(
                new SolidBrush(Color.Gold), 0, 0, this.maxWidth, this.maxHeight);

            pen = new Pen(Color.Blue);
            brush = new SolidBrush(Color.DarkBlue);
            signature = new ArrayList(50);

            this.MouseDown += new MouseEventHandler(MouseDownHandler);
            this.MouseMove += new MouseEventHandler(MouseMoveHandler);
            this.MouseUp   += new MouseEventHandler(MouseUpHandler);
        }

        public void Clear() 
        {
            numPoints = 0;
            signature.Clear();
            this.graphics.FillRectangle(
                new SolidBrush(Color.Gold), 0, 0, this.maxWidth, this.maxHeight);
            Refresh();
        }

        protected override void OnPaint(PaintEventArgs e) 
        {
            e.Graphics.DrawImage(this.bitmap, 0, 0);
        }

        private void MouseMoveHandler(object sender, MouseEventArgs e) 
        {
            int x, y;
                
            if (this.hasCapture) 
            {
                if (e.X < this.penWidth || e.X >= this.maxWidth - this.penWidth || e.Y < this.penWidth || e.Y >= this.maxHeight - this.penWidth)
                {
                    return;
                }

                x = e.X;
                y = e.Y;

                numPoints += 2;
                if (this.oldX != x && this.oldY != y) 
                {
                    Rectangle   rectDraw;

                    rectDraw = new Rectangle(Math.Min(x, this.oldX), Math.Min(y, this.oldY), Math.Abs(this.oldX - x) + 1, Math.Abs(this.oldY - y) + 1);
                    stroke.Add(new Point(x, y));

                    DrawSignatureLine(this.oldX, this.oldY, x, y, ref rectDraw);
                    Invalidate(rectDraw);
           
                    this.oldX = x;
                    this.oldY = y;
                }
            }
        }

        private void MouseDownHandler(object sender, MouseEventArgs e) 
        {
            if (e.X < this.penWidth || e.X >= this.maxWidth - this.penWidth || e.Y < this.penWidth || e.Y >= this.maxHeight - this.penWidth)
            {
                return;
            }

            this.hasCapture = true;
            this.Capture = true;
        
            this.oldX = e.X;
            this.oldY = e.Y;
		
            this.graphics.DrawLine(
                this.pen, this.oldX, this.oldY, this.oldX, this.oldY);
            
            this.Invalidate(new Rectangle(this.oldX, this.oldY, 1, 1));

            numPoints += 2;
            stroke = new Stroke(50);
            stroke.Add(new Point(e.X, e.Y));
            signature.Add(stroke);
        }

        private void MouseUpHandler(object sender, MouseEventArgs e) 
        {
            if (null != stroke) 
            {
                if (e.X >= penWidth && e.X < this.maxWidth - this.penWidth && e.Y >= this.penWidth && e.Y < this.maxHeight - this.penWidth)
                {
                    this.oldX = e.X;
                    this.oldY = e.Y;

                    if (this.oldX != e.X && this.oldY != e.Y) 
                    {
                        numPoints += 2;
                        stroke.Add(new Point(e.X, e.Y));
                    }
                    stroke = null;
                }
            }

            this.hasCapture = false;
        }

		public delegate void RefreshDelegate();

        public void DisplaySignature()
        {
            Rectangle rect = new Rectangle(0, 0, 0, 0);

            this.graphics.FillRectangle(
                new SolidBrush(Color.Gold), 0, 0, this.maxWidth, this.maxHeight);

            foreach (Stroke s in signature) 
            {
                if (s != null) 
				 {
                    Point[] pa = s.ToPointArray();

                    int len = pa.Length;
                    if (len > 1) 
                    {
                        Point prev = pa[0];
                        for (int i=1; i < len; i++) 
                        {
                            DrawSignatureLine(prev.X, prev.Y, pa[i].X, pa[i].Y, ref rect);
                            prev = pa[i];
                        }
                    } 
                    else if (1 == len) 
                    {
                        Point pt = pa[0];
                        this.bitmap.SetPixel(pt.X, pt.Y, Color.DarkBlue);
                        DrawSignatureLine(pt.X, pt.Y, pt.X + 1, pt.Y + 1, ref rect);
                    }
                }
            }

			this.Invoke(new RefreshDelegate(Refresh));
            //this.Refresh();
        }

        private void DrawSignatureLine(int startX, int startY, int endX, int endY, ref Rectangle rectDraw)
        {
            int offset = 1;

            /// Draw line from last hit point to current hit point	
            ///
            this.graphics.DrawLine(this.pen, startX, startY, endX, endY);
            if (Math.Abs(endX - startX) > Math.Abs(endY - startY))
            {
                for (int i = 0; i < penWidth - 1; ++i)
                {
                    this.graphics.DrawLine(this.pen, startX, startY + offset, endX, endY + offset);
                    offset = offset > 0 ? -offset : (-offset) + 1;
                }

                rectDraw.Y = Math.Min(endY, startY) + 1 - Math.Abs(offset);
                rectDraw.Height = Math.Abs(startY - endY) + 1 + Math.Abs(offset);
            }
            else
            {
                for (int i = 0; i < penWidth - 1; ++i)
                {
                    this.graphics.DrawLine(this.pen, startX + offset, startY, endX + offset, endY);
                    offset = offset > 0 ? -offset : (-offset) + 1;
                }

                rectDraw.X = Math.Min(endX, startX) + 1 - Math.Abs(offset);
                rectDraw.Width = Math.Abs(startX - endX) + 1 + Math.Abs(offset);
            }
        }
    }
}