Winform 图片鼠标滚动查看(放大,缩小,旋转,拖动查看)[日常随笔]

方法千千万,我只是其中一笔[通过控制PictureBox来控制图片,图片完全施展在控件中]...几久不做,还真有点陌生!

窗体构造中添加鼠标滚动:

 /// <summary>
         /// 窗体构造方法
         /// </summary>
         public CandidateForm()
         {
             InitializeComponent();
             this.MouseWheel += new MouseEventHandler(CandidateForm_MouseWheel);
         }

滚动监听:并且保持图片正中

 /// <summary>
         /// 鼠标滚动
         /// </summary>
         /// <param name="sender"></param>
         /// <param name="e"></param>
         private void CandidateForm_MouseWheel(object sender, MouseEventArgs e)
         {
             this.pic.Dock = DockStyle.None;
             this.pic.BorderStyle = BorderStyle.FixedSingle;
             Size size = this.pic.Size;
             size.Width += e.Delta;
             if (size.Width > pic.Image.Width)
             {
                 pic.Width = pic.Image.Width;
                 pic.Height = pic.Image.Height;
             }
             else if (size.Width * pic.Image.Height / pic.Image.Width < pic.Parent.Height - )
             {
                 return;
             }
             else
             {
                 pic.Width = size.Width;
                 pic.Height = size.Width * pic.Image.Height / pic.Image.Width;
             }
             pic.Left = (pic.Parent.Width - pic.Width) / ;
             pic.Top = (pic.Parent.Height - pic.Height) / ;
         }

旋转:

 private void 左旋ToolStripMenuItem_Click(object sender, EventArgs e)
         {
             if (basicBt != null)
             {
                 basicBt = Tools.Rotate(basicBt, );
                 height = this.pic.Width;
                 width = this.pic.Height;
                 setBasicPb(basicBt);
             }
         }

         private void 右旋ToolStripMenuItem_Click(object sender, EventArgs e)
         {
             if (basicBt != null)
             {
                 basicBt = Tools.Rotate(basicBt, );
                 height = this.pic.Width;
                 width = this.pic.Height;
                 setBasicPb(basicBt);
             }
         }

拖动直接在鼠标点击事件中,对PictureBox位置根据鼠标拖动进行处理就好.关键代码:

 //拖动
             if (canDrag)
             {
                pic.Location =
                     new Point(pic.Left + e.X - p0.X, pic.Top + e.Y - p0.Y);
             }

如果不是特意做图片查看,一般还会有对图片进行处理的功能,及需要用到鼠标拖动啊,针对原图片的定位等等~~ 则要用到图片的相对位置定位.

因为使用的是通过改变PictureBox的方法进行处理,所以只需算出比例即可.

    rate = (double)pic.Width / (double)pic.Image.Width;