C# 实现QQ式截图功能实例代码

using System;using System.Collections.Generic;using System.ComponentModel;using System.Data;using System.Drawing;using System.Linq;using System.Text;using System.Windows.Forms;using System.Drawing.Drawing2D;using System.Drawing.Imaging;using ImageClassLib;namespace ImageShear{  public partial class Demo: Form  {    public Demo()    {      InitializeComponent();    }    #region 点击打开图像    public string strHeadImagePath; //打开图片的路径    Bitmap Bi; //定义位图对像    private void button1_Click(object sender, EventArgs e)    {      openFileDialog1.Filter = "*.gif|*.jpg|*.JPEG|*.JPEG|*.bmp|*.bmp";     //设置读取图片类型      if (openFileDialog1.ShowDialog() == DialogResult.OK)      {        try        {          strHeadImagePath = openFileDialog1.FileName;          //this.Show(strHeadImagePath);          Bi = new Bitmap(strHeadImagePath); //使用打开的图片路径创建位图对像          ImageCut1 IC = new ImageCut1(40, 112, this.pictureBox1.Width, this.pictureBox1.Height);   //实例化ImageCut类，四个参数据分别表示为：x、y、width、heigth，（40、112）表示pictureBox1的Lcation的坐标，（120、144）表示pictureBox1控件的宽度和高度          this.pictureBox1.Image = IC.KiCut1((Bitmap)(this.GetSelectImage(this.pictureBox1.Width, this.pictureBox1.Height)));   //（120、144）表示pictureBox1控件的宽度和高度          //this.pictureBox1.Image = (this.GetSelectImage(120, 144));        }        catch (Exception ex)        {          MessageBox.Show("格式不对");          ex.ToString();        }      }    }    #endregion    #region 定义显示图像方法，即将打开的图像在pictureBox1控件显示    public void Show(string strHeadImagePath)    {      this.pictureBox1.Load(@strHeadImagePath);  //    }    #endregion    #region 获取图像    /// <summary>    /// 获取指定宽度和高度的图像即使图片和pictureBox1控件一样宽和高，返回值为图片Image    /// </summary>    /// <param name="Width表示宽"></param>    /// <param name="Height表示高"></param>    /// <returns></returns>    public Image GetSelectImage(int Width, int Height)    {      //Image initImage = this.pictureBox1.Image;      Image initImage = Bi;      //原图宽高均小于模版，不作处理，直接保存       if (initImage.Width <= Width && initImage.Height <= Height)      {        //initImage.Save(fileSaveUrl, System.Drawing.Imaging.ImageFormat.Jpeg);        return initImage;      }      else      {        //原始图片的宽、高         int initWidth = initImage.Width;        int initHeight = initImage.Height;        //非正方型先裁剪为正方型         if (initWidth != initHeight)        {          //截图对象           System.Drawing.Image pickedImage = null;          System.Drawing.Graphics pickedG = null;          //宽大于高的横图           if (initWidth > initHeight)          {            //对象实例化             pickedImage = new System.Drawing.Bitmap(initHeight, initHeight);            pickedG = System.Drawing.Graphics.FromImage(pickedImage);            //设置质量             pickedG.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic;            pickedG.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;            //定位             Rectangle fromR = new Rectangle((initWidth - initHeight) / 2, 0, initHeight, initHeight);            Rectangle toR = new Rectangle(0, 0, initHeight, initHeight);            //画图             pickedG.DrawImage(initImage, toR, fromR, System.Drawing.GraphicsUnit.Pixel);            //重置宽             initWidth = initHeight;          }          //高大于宽的竖图           else          {            //对象实例化            pickedImage = new System.Drawing.Bitmap(initWidth, initWidth);            pickedG = System.Drawing.Graphics.FromImage(pickedImage);            //设置质量             pickedG.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic;            pickedG.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;            //定位             Rectangle fromR = new Rectangle(0, (initHeight - initWidth) / 2, initWidth, initWidth);            Rectangle toR = new Rectangle(0, 0, initWidth, initWidth);            //画图             pickedG.DrawImage(initImage, toR, fromR, System.Drawing.GraphicsUnit.Pixel);            //重置高             initHeight = initWidth;          }          initImage = (System.Drawing.Image)pickedImage.Clone();          //        //释放截图资源           pickedG.Dispose();          pickedImage.Dispose();        }        return initImage;      }    }    #endregion    #region 点击button2按钮事件    private void button2_Click(object sender, EventArgs e)    {      this.label1.Text = "裁剪后的图片宽度："+this.pictureBox2.Width.ToString();      this.label2.Text = "裁剪后的图片高度："+this.pictureBox2.Height.ToString();    }    #endregion    #region 缩放、裁剪图像用到的变量    /// <summary>    ///     /// </summary>    int x1;   //鼠标按下时横坐标    int y1;   //鼠标按下时纵坐标    int width; //所打开的图像的宽    int heigth; //所打开的图像的高    bool HeadImageBool = false;  // 此布尔变量用来判断pictureBox1控件是否有图片    #endregion    #region 画矩形使用到的变量    Point p1;  //定义鼠标按下时的坐标点    Point p2;  //定义移动鼠标时的坐标点    Point p3;  //定义松开鼠标时的坐标点    #endregion    #region 鼠标按下时发生的事件    private void pictureBox1_MouseDown(object sender, MouseEventArgs e)    {      this.Cursor = Cursors.Cross;      this.p1 = new Point(e.X, e.Y);      x1 = e.X;      y1 = e.Y;      if (this.pictureBox1.Image != null)      {        HeadImageBool = true;      }      else      {        HeadImageBool = false;      }    }    #endregion    #region 移动鼠标发生的事件    private void pictureBox1_MouseMove(object sender, MouseEventArgs e)    {      if (this.Cursor == Cursors.Cross)      {        this.p2 = new Point(e.X, e.Y);        if ((p2.X - p1.X) > 0 && (p2.Y - p1.Y) > 0)   //当鼠标从左上角向开始移动时P3坐标        {          this.p3 = new Point(p1.X, p1.Y);        }        if ((p2.X - p1.X) < 0 && (p2.Y - p1.Y) > 0)   //当鼠标从右上角向左下方向开始移动时P3坐标        {          this.p3 = new Point(p2.X, p1.Y);        }        if ((p2.X - p1.X) > 0 && (p2.Y - p1.Y) < 0)   //当鼠标从左下角向上开始移动时P3坐标        {          this.p3 = new Point(p1.X, p2.Y);        }        if ((p2.X - p1.X) < 0 && (p2.Y - p1.Y) < 0)   //当鼠标从右下角向左方向上开始移动时P3坐标        {          this.p3 = new Point(p2.X, p2.Y);        }        this.pictureBox1.Invalidate(); //使控件的整个图面无效，并导致重绘控件      }    }    #endregion    #region 松开鼠标发生的事件，实例化ImageCut1类对像    ImageCut1 IC1; //定义所画矩形的图像对像    private void pictureBox1_MouseUp(object sender, MouseEventArgs e)    {      if (HeadImageBool)      {        width = this.pictureBox1.Image.Width;        heigth = this.pictureBox1.Image.Height;        if ((e.X - x1) > 0 && (e.Y - y1) > 0)  //当鼠标从左上角向右下方向开始移动时发生        {          IC1 = new ImageCut1(x1, y1, Math.Abs(e.X - x1), Math.Abs(e.Y - y1));  //实例化ImageCut1类        }        if ((e.X - x1) < 0 && (e.Y - y1) > 0)  //当鼠标从右上角向左下方向开始移动时发生        {          IC1 = new ImageCut1(e.X, y1, Math.Abs(e.X - x1), Math.Abs(e.Y - y1));  //实例化ImageCut1类        }        if ((e.X - x1) > 0 && (e.Y - y1) < 0)  //当鼠标从左下角向右上方向开始移动时发生        {          IC1 = new ImageCut1(x1, e.Y, Math.Abs(e.X - x1), Math.Abs(e.Y - y1));  //实例化ImageCut1类        }        if ((e.X - x1) < 0 && (e.Y - y1) < 0)  //当鼠标从右下角向左上方向开始移动时发生        {          IC1 = new ImageCut1(e.X, e.Y, Math.Abs(e.X - x1), Math.Abs(e.Y - y1));   //实例化ImageCut1类        }        this.pictureBox2.Width = (IC1.KiCut1((Bitmap)(this.pictureBox1.Image))).Width;        this.pictureBox2.Height = (IC1.KiCut1((Bitmap)(this.pictureBox1.Image))).Height;        this.pictureBox2.Image = IC1.KiCut1((Bitmap)(this.pictureBox1.Image));        this.Cursor = Cursors.Default;      }      else      {        this.Cursor = Cursors.Default;      }    }    #endregion    #region 获取所选矩形图像    /// <summary>    ///     /// </summary>    /// <param name="Width"></param>    /// <param name="Height"></param>    /// <returns></returns>    public Image GetSelectImage1(int Width, int Height)    {      Image initImage = this.pictureBox1.Image;      //Image initImage = Bi;      //原图宽高均小于模版，不作处理，直接保存       if (initImage.Width <= Width && initImage.Height <= Height)      {        //initImage.Save(fileSaveUrl, System.Drawing.Imaging.ImageFormat.Jpeg);        return initImage;      }      else      {        //原始图片的宽、高         int initWidth = initImage.Width;        int initHeight = initImage.Height;        //非正方型先裁剪为正方型         if (initWidth != initHeight)        {          //截图对象           System.Drawing.Image pickedImage = null;          System.Drawing.Graphics pickedG = null;          //宽大于高的横图           if (initWidth > initHeight)          {            //对象实例化             pickedImage = new System.Drawing.Bitmap(initHeight, initHeight);            pickedG = System.Drawing.Graphics.FromImage(pickedImage);            //设置质量             pickedG.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic;            pickedG.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;            //定位             Rectangle fromR = new Rectangle((initWidth - initHeight) / 2, 0, initHeight, initHeight);            Rectangle toR = new Rectangle(0, 0, initHeight, initHeight);            //画图             pickedG.DrawImage(initImage, toR, fromR, System.Drawing.GraphicsUnit.Pixel);            //重置宽             initWidth = initHeight;          }          //高大于宽的竖图           else          {            //对象实例化            pickedImage = new System.Drawing.Bitmap(initWidth, initWidth);            pickedG = System.Drawing.Graphics.FromImage(pickedImage);            //设置质量             pickedG.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic;            pickedG.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;            //定位             Rectangle fromR = new Rectangle(0, (initHeight - initWidth) / 2, initWidth, initWidth);            Rectangle toR = new Rectangle(0, 0, initWidth, initWidth);            //画图             pickedG.DrawImage(initImage, toR, fromR, System.Drawing.GraphicsUnit.Pixel);            //重置高             initHeight = initWidth;          }          initImage = (System.Drawing.Image)pickedImage.Clone();          //        //释放截图资源           pickedG.Dispose();          pickedImage.Dispose();        }        return initImage;      }    }    #endregion    #region 重新绘制pictureBox1控件，即移动鼠标画矩形    private void pictureBox1_Paint(object sender, PaintEventArgs e)    {      if (HeadImageBool)      {        Pen p = new Pen(Color.Black, 1);//画笔        p.DashStyle = System.Drawing.Drawing2D.DashStyle.Dash;        //Bitmap bitmap = new Bitmap(strHeadImagePath);        Bitmap bitmap = Bi;        Rectangle rect = new Rectangle(p3, new Size(System.Math.Abs(p2.X - p1.X), System.Math.Abs(p2.Y - p1.Y)));        e.Graphics.DrawRectangle(p, rect);      }      else      {      }    }    #endregion  }}

using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Drawing;using System.Drawing.Drawing2D;using System.Drawing.Imaging;namespace ImageClassLib{  public class ImageCut1  {    #region 剪裁图片方法    /// <summary>     /// 剪裁 -- 用GDI+     /// </summary>     /// <param name="b">原始Bitmap,即需要裁剪的图片</param>     /// <param name="StartX">开始坐标X</param>     /// <param name="StartY">开始坐标Y</param>     /// <param name="iWidth">宽度</param>     /// <param name="iHeight">高度</param>     /// <returns>剪裁后的Bitmap</returns>     public Bitmap KiCut1(Bitmap b)     {       if (b == null)       {         return null;       }           int w = b.Width;       int h = b.Height;           if (X >= w || Y >= h)       {         return null;       }           if (X + Width > w)       {         Width = w - X;       }           if (Y + Height > h)       {         Height = h - Y;       }           try      {         Bitmap bmpOut = new Bitmap(Width, Height, PixelFormat.Format24bppRgb);             Graphics g = Graphics.FromImage(bmpOut);        // Create rectangle for displaying image.        Rectangle destRect = new Rectangle(0, 0, Width, Height);    //所画的矩形正确，它指定所绘制图像的位置和大小。 将图像进行缩放以适合该矩形。        // Create rectangle for source image.        Rectangle srcRect = new Rectangle(X, Y, Width, Height);   //srcRect参数指定要绘制的 image 对象的矩形部分。 将此部分进行缩放以适合 destRect 参数所指定的矩形。        g.DrawImage(b, destRect, srcRect, GraphicsUnit.Pixel);        //resultG.DrawImage(initImage, new System.Drawing.Rectangle(0, 0, side, side), new System.Drawing.Rectangle(0, 0, initWidth, initHeight), System.Drawing.GraphicsUnit.Pixel);        g.Dispose();         return bmpOut;       }       catch      {         return null;       }     }    #endregion    #region ImageCut1类的构造函数    public int X;     public int Y;     public int Width ;     public int Height;    /// <summary>    /// ImageCut1类的构造函数，ImageCut1类用来获取鼠标在pictureBox1控件所画矩形内的图像    /// </summary>    /// <param name="x表示鼠标在pictureBox1控件上按下时的横坐标"></param>    /// <param name="y表示鼠标在pictureBox1控件上按下时的纵坐标"></param>    /// <param name="width表示鼠标在pictureBox1控件上松开鼠标的宽度"></param>    /// <param name="heigth表示鼠标在pictureBox1控件上松开鼠标的高度"></param>    public ImageCut1(int x, int y, int width, int heigth)    {      X = x;      Y = y;      Width = width;      Height = heigth;    }    #endregion  }}