Winform 圖片鼠標滾動查看(放大,縮小,旋轉,拖動查看)[日常隨筆]

方法千千萬,我只是其中一筆[通過控制PictureBox來控制圖片,圖片完全施展在控件中]...幾久不做,還真有點陌生!

窗體構造中添加鼠標滾動:

/// <summary>
        /// 窗體構造方法
        /// </summary>
        public CandidateForm()
        {
            InitializeComponent();
            this.MouseWheel += new MouseEventHandler(CandidateForm_MouseWheel);
        }

滾動監聽:並且保持圖片正中

/// <summary>
        /// 鼠標滾動
        /// </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 - 200)
            {
                return;
            }
            else
            {
                pic.Width = size.Width;
                pic.Height = size.Width * pic.Image.Height / pic.Image.Width;
            }
            pic.Left = (pic.Parent.Width - pic.Width) / 2;
            pic.Top = (pic.Parent.Height - pic.Height) / 2;
        }

旋轉:

private void 左旋ToolStripMenuItem_Click(object sender, EventArgs e)
        {
            if (basicBt != null)
            {
                basicBt = Tools.Rotate(basicBt, 90);
                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, 270);
                height = this.pic.Width;
                width = this.pic.Height;
                setBasicPb(basicBt);
            }
        }

 

拖動直接在鼠標點擊事件中,對PictureBox位置根據鼠標拖動進行處理就好.關鍵代碼:

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

 

如果不是特意做圖片查看,一般還會有對圖片進行處理的功能,及需要用到鼠標拖動啊,針對原圖片的定位等等~~ 則要用到圖片的相對位置定位.

因為使用的是通過改變PictureBox的方法進行處理,所以只需算出比例即可.

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