C＃模拟QQ截屏功能
可以利用Graphics类的CopyFromScreen方法来实现屏幕截取，舍弃了比较麻烦的API函数，只要几句代码就能实现了，而且这个这个方法能实现只抓取部分区域的屏幕，可以实现类似qq抓屏的功能。
using System;using System.Collections.Generic;using System.Text;using System.Drawing;using System.Drawing.Imaging;using System.Windows.Forms;namespace ConsoleApplication1
{
class Program
{
static void Main(string[] args) { //获得当前屏幕的分辨率
Screen scr = Screen.PrimaryScreen;
Rectangle rc = scr.Bounds;
int iWidth = rc.Width;
Screen scr = Screen.PrimaryScreen; Rectangle rc = scr.Bounds; int iWidth = rc.Width; int iHeight = rc.Height; //创建一个和屏幕一样大的Bitmap
Image myImage = new Bitmap(iWidth, iHeight);
Image myImage = new Bitmap(iWidth, iHeight); //从一个继承自Image类的对象中创建Graphics对象
Graphics g = Graphics.FromImage(myImage); //抓屏并拷贝到myimage里
g.CopyFromScreen(new Point(0, 0), new Point(0, 0), new Size(iWidth, iHeight));
//保存为文件
myImage.Save(@"c:/1.jpeg");
}
}
}
g.CopyFromScreen(new Point(0, 0), new Point(0, 0), new Size(iWidth, iHeight));//保存为文件
myImage.Save(@"c:/1.jpeg"); } }}以上内容转自lijgame的blog，在此对作者表示感谢！
原文地址：http://blog.csdn.net/lijgame/archive/2006/12/18/1447921.aspx
现在就文中的“实现QQ截屏”功能继续研究如下。
1、首先要实现在屏幕上画图，即：可以在屏幕上画出一个矩形框，双击该矩形框将截取矩形框内的屏幕。
目前在屏幕上画图的C＃实现代码如下：
[DllImport("User32.dll")]
public extern static System.IntPtr GetDC(System.IntPtr hWnd);
private void button19_Click(object sender, EventArgs e)
{
System.IntPtr DesktopHandle = GetDC(System.IntPtr.Zero);
Graphics g = Graphics.FromHdc(DesktopHandle);
g.DrawRectangle(new Pen(Color.Red),new Rectangle(10,10,100,100));
}
public extern static System.IntPtr GetDC(System.IntPtr hWnd);
private void button19_Click(object sender, EventArgs e)
{
System.IntPtr DesktopHandle = GetDC(System.IntPtr.Zero);
Graphics g = Graphics.FromHdc(DesktopHandle);
g.DrawRectangle(new Pen(Color.Red),new Rectangle(10,10,100,100));
}
需要用到可恶的API，实在不想用这种方法来实现！
2、研究出QQ屏幕上画图的真相
继续研究QQ截图的功能，发现当点击“截图”按钮之后，屏幕变成静止的了，原先网页上跳动的东西都不动了，哈哈，原因很简单，QQ截取了整个屏幕，然后用这张静止的屏幕覆盖全屏，真是精妙的解决办法啊！
于是用C＃实现是：
建一个子窗体ScreenForm ，在窗体上放一个pictureBox和一个label控件。ScreenForm代码如下：
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
namespace copyScreen
{
public partial class ScreenForm : Form
{
public ScreenForm()
{
InitializeComponent();
}
public event copyToFatherTextBox copytoFather; //截屏完毕后交个父窗体处理截图
public bool begin = false; //是否开始截屏
public bool isDoubleClick = false;
public Point firstPoint = new Point(0, 0); //鼠标第一点
public Point secondPoint = new Point(0, 0); //鼠标第二点
public Image cachImage = null; //用来缓存截获的屏幕
public int halfWidth = 0;//保存屏幕一半的宽度
public int halfHeight = 0;//保存屏幕一般的高度
/*复制整个屏幕,并让窗体填充屏幕*/
public void copyScreen()
{
Rectangle r = Screen.PrimaryScreen.Bounds;
Image img = new Bitmap(r.Width, r.Height);
Graphics g = Graphics.FromImage(img);
g.CopyFromScreen(new Point(0, 0), new Point(0, 0), r.Size);
//窗体最大化，及相关处理
this.Width = r.Width;
this.Height = r.Height;
this.Left = 0;
this.Top = 0;
pictureBox1.Width = r.Width;
pictureBox1.Height = r.Height;
pictureBox1.BackgroundImage = img;
cachImage = img;
halfWidth = r.Width / 2;
halfHeight = r.Height / 2;
this.Cursor = new Cursor(GetType(), "MyCursor.cur");
}
private void ScreenForm_Load(object sender, EventArgs e)
{
copyScreen();
}
/*鼠标按下时开始截图*/
private void pictureBox1_MouseDown(object sender, MouseEventArgs e)
{
if(!isDoubleClick)
{
begin = true;
firstPoint = new Point(e.X, e.Y);
changePoint(e.X, e.Y);
msg.Visible = true;
}
}
/*鼠标移动时显示截取区域的边框*/
private void pictureBox1_MouseMove(object sender, MouseEventArgs e)
{
if (begin)
{
//获取新的右下角坐标
secondPoint = new Point(e.X, e.Y);
int minX = Math.Min(firstPoint.X, secondPoint.X);
int minY = Math.Min(firstPoint.Y, secondPoint.Y);
int maxX = Math.Max(firstPoint.X, secondPoint.X);
int maxY = Math.Max(firstPoint.Y, secondPoint.Y);
//重新画背景图
Image tempimage = new Bitmap(cachImage);
Graphics g = Graphics.FromImage(tempimage);
//画裁剪框
g.DrawRectangle(new Pen(Color.Red),minX,minY,maxX-minX,maxY-minY);
pictureBox1.Image = tempimage;
//计算坐标信息
msg.Text = "左上角坐标：(" + minX.ToString() + "," + minY.ToString() + ")\r\n";
msg.Text += "右下角坐标：(" + maxX.ToString() + "," + maxY.ToString() + ")\r\n";
msg.Text += "截图大小：" + (maxX - minX) + "×" + (maxY - minY) + "\r\n";
msg.Text += "双击任意地方结束截屏！";
changePoint((minX + maxX) / 2, (minY + maxY) / 2);
}
}
/*动态调整显示信息的位置,输入参数为当前截屏鼠标位置*/
public void changePoint(int x, int y)
{
if (x < halfWidth)
{
if (y < halfHeight)
{ msg.Top = halfHeight; msg.Left = halfWidth; }
else
{ msg.Top = 0; msg.Left = halfWidth; }
}
else
{
if (y < halfHeight)
{ msg.Top = halfHeight; msg.Left = 0; }
else
{ msg.Top = 0; msg.Left = 0; }
}
}
/*鼠标放开时截图操作完成*/
private void pictureBox1_MouseUp(object sender, MouseEventArgs e)
{
begin = false;
isDoubleClick = true; //之后再点击就是双击事件了
}
/*双击时截图时，通知父窗体完成截图操作，同时关闭本窗体*/
private void pictureBox1_DoubleClick(object sender, EventArgs e)
{
if (firstPoint != secondPoint)
{
int minX = Math.Min(firstPoint.X, secondPoint.X);
int minY = Math.Min(firstPoint.Y, secondPoint.Y);
int maxX = Math.Max(firstPoint.X, secondPoint.X);
int maxY = Math.Max(firstPoint.Y, secondPoint.Y);
Rectangle r = new Rectangle(minX, minY, maxX - minX, maxY - minY);
copytoFather(r);
}
this.Close();
//msg.Text = r.ToString();
}
}
}
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
namespace copyScreen
{
public partial class ScreenForm : Form
{
public ScreenForm()
{
InitializeComponent();
}
public event copyToFatherTextBox copytoFather; //截屏完毕后交个父窗体处理截图
public bool begin = false; //是否开始截屏
public bool isDoubleClick = false;
public Point firstPoint = new Point(0, 0); //鼠标第一点
public Point secondPoint = new Point(0, 0); //鼠标第二点
public Image cachImage = null; //用来缓存截获的屏幕
public int halfWidth = 0;//保存屏幕一半的宽度
public int halfHeight = 0;//保存屏幕一般的高度
/*复制整个屏幕,并让窗体填充屏幕*/
public void copyScreen()
{
Rectangle r = Screen.PrimaryScreen.Bounds;
Image img = new Bitmap(r.Width, r.Height);
Graphics g = Graphics.FromImage(img);
g.CopyFromScreen(new Point(0, 0), new Point(0, 0), r.Size);
//窗体最大化，及相关处理
this.Width = r.Width;
this.Height = r.Height;
this.Left = 0;
this.Top = 0;
pictureBox1.Width = r.Width;
pictureBox1.Height = r.Height;
pictureBox1.BackgroundImage = img;
cachImage = img;
halfWidth = r.Width / 2;
halfHeight = r.Height / 2;
this.Cursor = new Cursor(GetType(), "MyCursor.cur");
}
private void ScreenForm_Load(object sender, EventArgs e)
{
copyScreen();
}
/*鼠标按下时开始截图*/
private void pictureBox1_MouseDown(object sender, MouseEventArgs e)
{
if(!isDoubleClick)
{
begin = true;
firstPoint = new Point(e.X, e.Y);
changePoint(e.X, e.Y);
msg.Visible = true;
}
}
/*鼠标移动时显示截取区域的边框*/
private void pictureBox1_MouseMove(object sender, MouseEventArgs e)
{
if (begin)
{
//获取新的右下角坐标
secondPoint = new Point(e.X, e.Y);
int minX = Math.Min(firstPoint.X, secondPoint.X);
int minY = Math.Min(firstPoint.Y, secondPoint.Y);
int maxX = Math.Max(firstPoint.X, secondPoint.X);
int maxY = Math.Max(firstPoint.Y, secondPoint.Y);
//重新画背景图
Image tempimage = new Bitmap(cachImage);
Graphics g = Graphics.FromImage(tempimage);
//画裁剪框
g.DrawRectangle(new Pen(Color.Red),minX,minY,maxX-minX,maxY-minY);
pictureBox1.Image = tempimage;
//计算坐标信息
msg.Text = "左上角坐标：(" + minX.ToString() + "," + minY.ToString() + ")\r\n";
msg.Text += "右下角坐标：(" + maxX.ToString() + "," + maxY.ToString() + ")\r\n";
msg.Text += "截图大小：" + (maxX - minX) + "×" + (maxY - minY) + "\r\n";
msg.Text += "双击任意地方结束截屏！";
changePoint((minX + maxX) / 2, (minY + maxY) / 2);
}
}
/*动态调整显示信息的位置,输入参数为当前截屏鼠标位置*/
public void changePoint(int x, int y)
{
if (x < halfWidth)
{
if (y < halfHeight)
{ msg.Top = halfHeight; msg.Left = halfWidth; }
else
{ msg.Top = 0; msg.Left = halfWidth; }
}
else
{
if (y < halfHeight)
{ msg.Top = halfHeight; msg.Left = 0; }
else
{ msg.Top = 0; msg.Left = 0; }
}
}
/*鼠标放开时截图操作完成*/
private void pictureBox1_MouseUp(object sender, MouseEventArgs e)
{
begin = false;
isDoubleClick = true; //之后再点击就是双击事件了
}
/*双击时截图时，通知父窗体完成截图操作，同时关闭本窗体*/
private void pictureBox1_DoubleClick(object sender, EventArgs e)
{
if (firstPoint != secondPoint)
{
int minX = Math.Min(firstPoint.X, secondPoint.X);
int minY = Math.Min(firstPoint.Y, secondPoint.Y);
int maxX = Math.Max(firstPoint.X, secondPoint.X);
int maxY = Math.Max(firstPoint.Y, secondPoint.Y);
Rectangle r = new Rectangle(minX, minY, maxX - minX, maxY - minY);
copytoFather(r);
}
this.Close();
//msg.Text = r.ToString();
}
}
}
界面如下：
本程序下载： CODE 演示版：Demo
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