在顶部Form1，我有：
Bitmap bitmap;
在构造函数中：
bitmap = (Bitmap)sc.CaptureScreen();
创建 100 个屏幕截图：
for (int i = 0; i < 100; i++)
{
bitmap.Save(@"D:\ffmpegtorun\ffmpeg-20130509-git-13cb6ed-win32-static\bin\Screenshots\" + "Screenshot" + i.ToString("D6") + ".Jpg", ImageFormat.Jpeg);
}
把截图放到pictureBox1：
pictureBox1.Image = bitmap = new Bitmap(@"D:\ffmpegtorun\ffmpeg-20130509-git-13cb6ed-win32-static\bin\Screenshots\Screenshot000000.jpg");
然后在pictureBox1我正在做的绘画活动中：
private void pictureBox1_Paint(object sender, PaintEventArgs e)
{
int width = pictureBox1.Width;
int height = pictureBox1.Height;
// Draw the image with no shrinking or stretching.
e.Graphics.InterpolationMode = InterpolationMode.HighQualityBicubic;
e.Graphics.DrawImage(
bitmap,
new Rectangle(0, 0, width, height), // destination rectangle
0,
0, // upper-left corner of source rectangle
width, // width of source rectangle
height, // height of source rectangle
GraphicsUnit.Pixel,
null);
}
这是截屏类：
using System;
using System.Runtime.InteropServices;
using System.Drawing;
using System.Drawing.Imaging;
namespace ScreenShotDemo
{
/// <summary>
/// Provides functions to capture the entire screen, or a particular window, and save it to a file.
/// </summary>
public class ScreenCapture
{
/// <summary>
/// Creates an Image object containing a screen shot of the entire desktop
/// </summary>
/// <returns></returns>
public Image CaptureScreen()
{
return CaptureWindow(User32.GetDesktopWindow());
}
/// <summary>
/// Creates an Image object containing a screen shot of a specific window
/// </summary>
/// <param name="handle">The handle to the window. (In windows forms, this is obtained by the Handle property)</param>
/// <returns></returns>
public Image CaptureWindow(IntPtr handle)
{
// get te hDC of the target window
IntPtr hdcSrc = User32.GetWindowDC(handle);
// get the size
User32.RECT windowRect = new User32.RECT();
User32.GetWindowRect(handle, ref windowRect);
int width = windowRect.right - windowRect.left;
int height = windowRect.bottom - windowRect.top;
// create a device context we can copy to
IntPtr hdcDest = GDI32.CreateCompatibleDC(hdcSrc);
// create a bitmap we can copy it to,
// using GetDeviceCaps to get the width/height
IntPtr hBitmap = GDI32.CreateCompatibleBitmap(hdcSrc, width, height);
// select the bitmap object
IntPtr hOld = GDI32.SelectObject(hdcDest, hBitmap);
// bitblt over
GDI32.BitBlt(hdcDest, 0, 0, width, height, hdcSrc, 0, 0, GDI32.SRCCOPY);
// restore selection
GDI32.SelectObject(hdcDest, hOld);
// clean up
GDI32.DeleteDC(hdcDest);
User32.ReleaseDC(handle, hdcSrc);
// get a .NET image object for it
Image img = Image.FromHbitmap(hBitmap);
// free up the Bitmap object
GDI32.DeleteObject(hBitmap);
return img;
}
/// <summary>
/// Captures a screen shot of a specific window, and saves it to a file
/// </summary>
/// <param name="handle"></param>
/// <param name="filename"></param>
/// <param name="format"></param>
public void CaptureWindowToFile(IntPtr handle, string filename, ImageFormat format)
{
Image img = CaptureWindow(handle);
img.Save(filename, format);
}
/// <summary>
/// Captures a screen shot of the entire desktop, and saves it to a file
/// </summary>
/// <param name="filename"></param>
/// <param name="format"></param>
public void CaptureScreenToFile(string filename, ImageFormat format)
{
Image img = CaptureScreen();
img.Save(filename, format);
}
/// <summary>
/// Helper class containing Gdi32 API functions
/// </summary>
private class GDI32
{
public const int SRCCOPY = 0x00CC0020; // BitBlt dwRop parameter
[DllImport("gdi32.dll")]
public static extern bool BitBlt(IntPtr hObject, int nXDest, int nYDest,
int nWidth, int nHeight, IntPtr hObjectSource,
int nXSrc, int nYSrc, int dwRop);
[DllImport("gdi32.dll")]
public static extern IntPtr CreateCompatibleBitmap(IntPtr hDC, int nWidth,
int nHeight);
[DllImport("gdi32.dll")]
public static extern IntPtr CreateCompatibleDC(IntPtr hDC);
[DllImport("gdi32.dll")]
public static extern bool DeleteDC(IntPtr hDC);
[DllImport("gdi32.dll")]
public static extern bool DeleteObject(IntPtr hObject);
[DllImport("gdi32.dll")]
public static extern IntPtr SelectObject(IntPtr hDC, IntPtr hObject);
}
/// <summary>
/// Helper class containing User32 API functions
/// </summary>
private class User32
{
[StructLayout(LayoutKind.Sequential)]
public struct RECT
{
public int left;
public int top;
public int right;
public int bottom;
}
[DllImport("user32.dll")]
public static extern IntPtr GetDesktopWindow();
[DllImport("user32.dll")]
public static extern IntPtr GetWindowDC(IntPtr hWnd);
[DllImport("user32.dll")]
public static extern IntPtr ReleaseDC(IntPtr hWnd, IntPtr hDC);
[DllImport("user32.dll")]
public static extern IntPtr GetWindowRect(IntPtr hWnd, ref RECT rect);
}
}
}
结果是这样的：
https://skydrive.live.com/redir?resid=EB1C71C44C3976D5!270&authkey=!ANAKzbwJI-3TQqE
图片不适合图片框。
但是，如果我现在用放大镜在它上面移动图片框，我会看到它很平滑，但图像不适合图片框：
https://skydrive.live.com/redir?resid=EB1C71C44C3976D5!271&authkey=!ALizvsyxrMuyVTk
这是放大镜的表格代码：
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using System.Drawing.Drawing2D;
using System.IO;
using System.Drawing.Imaging;
namespace Magnifier20070401
{
public partial class MagnifierForm : Form
{
private bool _doMove;
public MagnifierForm()
{
InitializeComponent();
_doMove = true;
FormBorderStyle = FormBorderStyle.None;
ShowInTaskbar = false;
TopMost = true;
Width = 150;
Height = 150;
GraphicsPath gp = new GraphicsPath();
gp.AddEllipse(ClientRectangle);
Region = new Region(gp);
mTimer = new Timer();
mTimer.Enabled = true;
mTimer.Interval = 20;
mTimer.Tick += new EventHandler(HandleTimer);
mScreenImage = new Bitmap(Screen.PrimaryScreen.Bounds.Width,
Screen.PrimaryScreen.Bounds.Height);
mStartPoint = new Point(500, 500);
mTargetPoint = new Point(500, 500);
speed = 0.35F;
zoom = 3.0F;
hidecursor = false;
hue = 30;
}
public MagnifierForm(bool MoveTheGlass, bool InTaskBar, int MagnifierWidth, int MagnifierHeight, Point MagnifierStartPoint, float SpeedFactor, float ChangeZoom, bool HideMouseCursor, float AdjustHue)
{
InitializeComponent();
FormBorderStyle = FormBorderStyle.None;
TopMost = true;
GraphicsPath gp = new GraphicsPath();
gp.AddEllipse(ClientRectangle);
Region = new Region(gp);
mTimer = new Timer();
mTimer.Enabled = true;
mTimer.Interval = 20;
mTimer.Tick += new EventHandler(HandleTimer);
mScreenImage = new Bitmap(Screen.PrimaryScreen.Bounds.Width,
Screen.PrimaryScreen.Bounds.Height);
_doMove = MoveTheGlass;
ShowInTaskbar = InTaskBar;
Width = MagnifierWidth;
Height = MagnifierHeight;
mStartPoint = MagnifierStartPoint;
mTargetPoint = MagnifierStartPoint;
speed = SpeedFactor;
zoom = ChangeZoom;
hidecursor = HideMouseCursor;
hue = AdjustHue;
}
protected override void OnShown(EventArgs e)
{
RepositionAndShow();
}
private delegate void RepositionAndShowDelegate();
private void RepositionAndShow()
{
if (InvokeRequired)
{
Invoke(new RepositionAndShowDelegate(RepositionAndShow));
}
else
{
Graphics g = Graphics.FromImage(mScreenImage);
g.CopyFromScreen(0, 0, 0, 0, new Size(mScreenImage.Width, mScreenImage.Height));
HSLAdjust.BitmapFunctions bf = new HSLAdjust.BitmapFunctions((Bitmap)mScreenImage);
bf.Hue(hue);
bf.Dispose();
g.Dispose();
if (hidecursor == true)
{
Cursor.Hide();
}
else
{
Cursor = Cursors.Cross;
}
Capture = true;
mCurrentPoint = Cursor.Position;
Show(); // to add here the bool of the Mouse Cursor to hide or not to hide
}
}
void HandleTimer(object sender, EventArgs e)
{
float dx = speed * (mTargetPoint.X - mCurrentPoint.X);
float dy = speed * (mTargetPoint.Y - mCurrentPoint.Y);
if (mFirstTime)
{
mFirstTime = false;
mCurrentPoint.X = mTargetPoint.X;
mCurrentPoint.Y = mTargetPoint.Y;
Left = (int)mCurrentPoint.X - Width / 2;
Top = (int)mCurrentPoint.Y - Height / 2;
return;
}
mCurrentPoint.X += dx;
mCurrentPoint.Y += dy;
if (Math.Abs(dx) < 1 && Math.Abs(dy) < 1)
{
mTimer.Enabled = false;
}
else
{
// Update location
Left = (int)mCurrentPoint.X - Width / 2;
Top = (int)mCurrentPoint.Y - Height / 2;
mLastMagnifierPosition = new Point((int)mCurrentPoint.X, (int)mCurrentPoint.Y);
}
Refresh();
}
protected override void OnMouseDown(MouseEventArgs e)
{
mOffset = new Point(Width / 2 - e.X, Height / 2 - e.Y);
mCurrentPoint = PointToScreen(new Point(e.X + mOffset.X, e.Y + mOffset.Y));
mTargetPoint = mCurrentPoint;
mTimer.Enabled = true;
}
protected override void OnMouseMove(MouseEventArgs e)
{
if (_doMove == true)
{
mTargetPoint = PointToScreen(new Point(e.X + mOffset.X, e.Y + mOffset.Y));
mTimer.Enabled = true;
}
}
protected override void OnPaintBackground(PaintEventArgs e)
{
/*if (mConfiguration.DoubleBuffered)
{
// Do not paint background (required for double buffering)!
}
else
{
base.OnPaintBackground(e);
}*/
base.OnPaintBackground(e);
}
protected override void OnPaint(PaintEventArgs e)
{
if (mBufferImage == null)
{
mBufferImage = new Bitmap(Width, Height);
}
Graphics bufferGrf = Graphics.FromImage(mBufferImage);
Graphics g;
/*if (mConfiguration.DoubleBuffered)
{
g = bufferGrf;
}
else
{*/
g = e.Graphics;
//}
if (mScreenImage != null)
{
Rectangle dest = new Rectangle(0, 0, Width, Height);
int w = (int)(Width / zoom);//mConfiguration.ZoomFactor);
int h = (int)(Height / zoom);//mConfiguration.ZoomFactor);
int x = Left - w / 2 + Width / 2;
int y = Top - h / 2 + Height / 2;
g.DrawImage(
mScreenImage,
dest,
x, y,
w, h,
GraphicsUnit.Pixel);
}
e.Graphics.DrawImage(mBufferImage, 0, 0, Width, Height);
}
//--- Data Members ---
#region Data Members
private bool hidecursor;
private float zoom;
private float hue;
private float speed;
private Timer mTimer;
private Image mBufferImage = null;
private Image mScreenImage = null;
private Point mStartPoint;
private PointF mTargetPoint;
private PointF mCurrentPoint;
private Point mOffset;
private bool mFirstTime = true;
private static Point mLastMagnifierPosition = Cursor.Position;
#endregion
// New code \\
protected override void OnMouseEnter(EventArgs e)
{
base.OnMouseEnter(e);
Point pt = Control.MousePosition;
int eX = pt.X - this.Left;
int eY = pt.Y - this.Top;
mOffset = new Point(0, 0);
mCurrentPoint = PointToScreen(new Point(eX + mOffset.X, eY + mOffset.Y));
mTargetPoint = mCurrentPoint;
mTimer.Enabled = true;
this.Capture = true;
}
protected override void OnMouseLeave(EventArgs e)
{
base.OnMouseLeave(e);
if (_doMove)
{
Left = (int)mCurrentPoint.X - Width / 2;
Top = (int)mCurrentPoint.Y - Height / 2;
}
}
protected override void OnMouseClick(MouseEventArgs e)
{
base.OnMouseClick(e);
if (_doMove == true)
{
_doMove = false;
}
else
{
_doMove = true;
}
}
}
}