C# 实现QQ式截图功能实例代码

usingSystem;

usingSystem.Collections.Generic;

usingSystem.ComponentModel;

usingSystem.Data;

usingSystem.Drawing;

usingSystem.Linq;

usingSystem.Text;

usingSystem.Windows.Forms;

usingSystem.Drawing.Drawing2D;

usingSystem.Drawing.Imaging;

usingImageClassLib;

namespaceImageShear

{

  publicpartialclassDemo: Form

  {

    publicDemo()

    {

      InitializeComponent();

    }

    #region 点击打开图像

    publicstringstrHeadImagePath;//打开图片的路径

    Bitmap Bi;//定义位图对像

    privatevoidbutton1_Click(objectsender, 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 =newBitmap(strHeadImagePath);//使用打开的图片路径创建位图对像

          ImageCut1 IC =newImageCut1(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

    publicvoidShow(stringstrHeadImagePath)

    {

      this.pictureBox1.Load(@strHeadImagePath); //

    }

    #endregion

    #region 获取图像

    ///

    ///

    ///

    ///

    publicImage GetSelectImage(intWidth,intHeight)

    {

      //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);

        returninitImage;

      }

      else

      {

        //原始图片的宽、高

        intinitWidth = initImage.Width;

        intinitHeight = 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 =newSystem.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 =newRectangle((initWidth - initHeight) / 2, 0, initHeight, initHeight);

            Rectangle toR =newRectangle(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 =newSystem.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 =newRectangle(0, (initHeight - initWidth) / 2, initWidth, initWidth);

            Rectangle toR =newRectangle(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();

        }

        returninitImage;

      }

    }

    #endregion

    #region 点击button2按钮事件

    privatevoidbutton2_Click(objectsender, 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

    ///

    intx1;  //鼠标按下时横坐标

    inty1;  //鼠标按下时纵坐标

    intwidth;//所打开的图像的宽

    intheigth;//所打开的图像的高

    boolHeadImageBool =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

    privatevoidpictureBox1_MouseDown(objectsender, MouseEventArgs e)

    {

      this.Cursor = Cursors.Cross;

      this.p1 =newPoint(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

    privatevoidpictureBox1_MouseMove(objectsender, MouseEventArgs e)

    {

      if(this.Cursor == Cursors.Cross)

      {

        this.p2 =newPoint(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 =newPoint(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 =newPoint(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 =newPoint(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 =newPoint(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

    privatevoidpictureBox1_MouseUp(objectsender, 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 =newImageCut1(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 =newImageCut1(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 =newImageCut1(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 =newImageCut1(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

    ///

    ///

    ///

    ///

    publicImage GetSelectImage1(intWidth,intHeight)

    {

      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);

        returninitImage;

      }

      else

      {

        //原始图片的宽、高

        intinitWidth = initImage.Width;

        intinitHeight = 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 =newSystem.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 =newRectangle((initWidth - initHeight) / 2, 0, initHeight, initHeight);

            Rectangle toR =newRectangle(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 =newSystem.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 =newRectangle(0, (initHeight - initWidth) / 2, initWidth, initWidth);

            Rectangle toR =newRectangle(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();

        }

        returninitImage;

      }

    }

    #endregion

    #region 重新绘制pictureBox1控件，即移动鼠标画矩形

    privatevoidpictureBox1_Paint(objectsender, PaintEventArgs e)

    {

      if(HeadImageBool)

      {

        Pen p =newPen(Color.Black, 1);//画笔

        p.DashStyle = System.Drawing.Drawing2D.DashStyle.Dash;

        //Bitmap bitmap = new Bitmap(strHeadImagePath);

        Bitmap bitmap = Bi;

        Rectangle rect =newRectangle(p3,newSize(System.Math.Abs(p2.X - p1.X), System.Math.Abs(p2.Y - p1.Y)));

        e.Graphics.DrawRectangle(p, rect);

      }

      else

      {

      }

    }

    #endregion

  }

}

usingSystem;

usingSystem.Collections.Generic;

usingSystem.Linq;

usingSystem.Text;

usingSystem.Drawing;

usingSystem.Drawing.Drawing2D;

usingSystem.Drawing.Imaging;

namespaceImageClassLib

{

  publicclassImageCut1

  {

    #region 剪裁图片方法

    ///

    /// 原始Bitmap,即需要裁剪的图片

    /// 开始坐标X

    /// 开始坐标Y

    /// 宽度

    /// 高度

    /// 剪裁后的Bitmap

    publicBitmap KiCut1(Bitmap b)

    {

      if(b ==null)

      {

        returnnull;

      }

      intw = b.Width;

      inth = b.Height;

      if(X >= w || Y >= h)

      {

        returnnull;

      }

      if(X + Width > w)

      {

        Width = w - X;

      }

      if(Y + Height > h)

      {

        Height = h - Y;

      }

      try

      {

        Bitmap bmpOut =newBitmap(Width, Height, PixelFormat.Format24bppRgb);

        Graphics g = Graphics.FromImage(bmpOut);

        // Create rectangle for displaying image.

        Rectangle destRect =newRectangle(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 =newRectangle(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();

        returnbmpOut;

      }

      catch

      {

        returnnull;

      }

    }

    #endregion

    #region ImageCut1类的构造函数

    publicintX;

    publicintY;

    publicintWidth ;

    publicintHeight;

    ///

    ///

    ///

    ///

    ///

    publicImageCut1(intx,inty,intwidth,intheigth)

    {

      X = x;

      Y = y;

      Width = width;

      Height = heigth;

    }

    #endregion

  }

}