这个截图模仿QQ截图，左键单击开始截图，鼠标移动出现方框确定截图尺寸，放开时为最终尺寸，双击鼠标弹出保存对话框进行保存。
还有一点就是，如果截图尺寸方框已经确定，移动鼠标到所选区域内时，鼠标会变手型，可以拖动该方框到任意地方进行截图。
建立ScreenCutter解决方案，在其下建立两个windows窗体，一个为MainForm，一个为ScreenBody。
在MainForm中放一个按钮，点击按钮时，获取整个桌面为背景图片，调用ScreenBody。
MainForm的代码为：
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
namespace MainForm
{
public partial class MainForm : Form
{
public MainForm()
{
InitializeComponent();
}
private void button1_Click(object sender, EventArgs e)
{
Image img = new Bitmap(Screen.AllScreens[0].Bounds.Width, Screen.AllScreens[0].Bounds.Height);
Graphics g = Graphics.FromImage(img);
g.CopyFromScreen(new Point(0, 0), new Point(0, 0), Screen.AllScreens[0].Bounds.Size);
ScreenBody body = new ScreenBody();
body.BackgroundImage = img;
body.Show();
}
}
}
然后设计ScreenBody，设置FormBorderStyle属性为None，再调用load、mousedoubleclick、mousedown、mousemove和mouseup事件即可。
代码如下：
using System;
using System.Data;
using System.Drawing;
using System.Drawing.Imaging;
using System.Text;
using System.Windows.Forms;
namespace MainForm
{
public partial class ScreenBody : Form
{
public ScreenBody()
{
InitializeComponent();
}
private Graphics MainPainter; //主画面
private Pen pen; //画笔
private bool isDowned; //判断鼠标是否按下
private bool RectReady; //矩形是否绘制完成
private Image baseImage; //基本图形(原来的画面)
private Rectangle Rect; //就是要保存的矩形
private Point downPoint; //鼠标按下的点
int tmpx;
int tmpy;
//加载初始化
private void ScreenBody_Load(object sender, EventArgs e)
{
this.WindowState = FormWindowState.Maximized;
MainPainter = this.CreateGraphics();
pen = new Pen(Brushes.Blue);
isDowned = false;
baseImage = this.BackgroundImage;
Rect = new Rectangle();
RectReady = false;
}
//双击保存
private void ScreenBody_MouseDoubleClick(object sender, MouseEventArgs e)
{
if (e.Button == MouseButtons.Left && Rect.Contains(e.X, e.Y))
{
Image memory = new Bitmap(Rect.Width, Rect.Height);
Graphics g = Graphics.FromImage(memory);
g.CopyFromScreen(Rect.X + 1, Rect.Y + 1, 0, 0, Rect.Size);
//Clipboard.SetImage(memory);
string filePath = null;
SaveFileDialog saveFileDialog1 = new SaveFileDialog();
saveFileDialog1.RestoreDirectory = true;
saveFileDialog1.Filter = "Image files (JPeg, Gif, Bmp, etc.)|*.jpg;*.jpeg;*.gif;*.bmp;*.tif; *.tiff; *.png|" +
"JPeg files (*.jpg;*.jpeg)|*.jpg;*.jpeg |GIF files (*.gif)|*.gif |BMP files (*.b" +
"mp)|*.bmp|Tiff files (*.tif;*.tiff)|*.tif;*.tiff|Png files (*.png)| *.png |All f" +
"iles (*.*)|*.*";
if (saveFileDialog1.ShowDialog() == DialogResult.OK)
{
filePath = saveFileDialog1.FileName.ToString();
memory.Save(filePath, ImageFormat.Jpeg);
}
this.Close();
}
}
//左击开始截图或移动，右击撤销
private void ScreenBody_MouseDown(object sender, MouseEventArgs e)
{
if (e.Button == MouseButtons.Left)
{
isDowned = true;
if (RectReady == false)
{
Rect.X = e.X;
Rect.Y = e.Y;
downPoint = new Point(e.X, e.Y);
}
if (RectReady == true)
{
tmpx = e.X;
tmpy = e.Y;
}
}
if (e.Button == MouseButtons.Right)
{
this.Close();
return;
}
}
//左键放开，截图方框完成
private void ScreenBody_MouseUp(object sender, MouseEventArgs e)
{
if (e.Button == MouseButtons.Left)
{
isDowned = false;
RectReady = true;
}
}
//鼠标移动，画框或者拖动
private void ScreenBody_MouseMove(object sender, MouseEventArgs e)
{
if (RectReady == false)
{
if (isDowned == true)
{
Image New = DrawScreen((Image)baseImage.Clone(), e.X, e.Y);
MainPainter.DrawImage(New, 0, 0);
New.Dispose();
}
}
if (RectReady == true)
{
if (Rect.Contains(e.X, e.Y))
{
this.Cursor = Cursors.Hand;
if (isDowned == true)
{
//和上一次的位置比较获取偏移量
Rect.X = Rect.X + e.X - tmpx;
Rect.Y = Rect.Y + e.Y - tmpy;
//记录现在的位置
tmpx = e.X;
tmpy = e.Y;
MoveRect((Image)baseImage.Clone(), Rect);
}
}
else
{
this.Cursor = Cursors.Arrow;
}
}
}
//画屏幕
private Image DrawScreen(Image back, int Mouse_x, int Mouse_y)
{
Graphics Painter = Graphics.FromImage(back);
DrawRect(Painter, Mouse_x, Mouse_y);
return back;
}
//画矩形
private void DrawRect(Graphics Painter, int Mouse_x, int Mouse_y)
{
int width = 0;
int heigth = 0;
try
{
if (Mouse_y < Rect.Y)
{
Rect.Y = Mouse_y;
heigth = downPoint.Y - Mouse_y;
}
else
{
heigth = Mouse_y - downPoint.Y;
}
if (Mouse_x < Rect.X)
{
Rect.X = Mouse_x;
width = downPoint.X - Mouse_x;
}
else
{
width = Mouse_x - downPoint.X;
}
}
catch (Exception ee)
{
MessageBox.Show("cuo");
}
finally
{
Rect.Size = new Size(width, heigth);
Painter.DrawRectangle(pen, Rect);
}
}
//移动矩形
private void MoveRect(Image image, Rectangle Rect)
{
Graphics Painter = Graphics.FromImage(image);
Painter.DrawRectangle(pen, Rect.X, Rect.Y, Rect.Width, Rect.Height);
MainPainter.DrawImage(image, 0, 0);
image.Dispose();
}
}
}