核心步驟：

①新建Point類型全局變量mouseDownPoint，記錄拖拽過程中鼠標位置；

②MouseDown事件記錄Cursor位置；

③MouseMove事件計算移動矢量，并更新pictureBox1.Location。

代碼： private void pictureBox1_MouseDown(object sender, MouseEventArgs e){if (e.Button == MouseButtons.Left){mouseDownPoint.X = Cursor.Position.X; //記錄鼠標左鍵按下時位置mouseDownPoint.Y = Cursor.Position.Y; isMove = true;pictureBox1.Focus(); //鼠標滾輪事件(縮放時)需要picturebox有焦點 }}private void pictureBox1_MouseUp(object sender, MouseEventArgs e){if (e.Button == MouseButtons.Left){isMove = false; }}private void pictureBox1_MouseMove(object sender, MouseEventArgs e){pictureBox1.Focus(); //鼠標在picturebox上時才有焦點，此時可以縮放if (isMove){int x, y; //新的pictureBox1.Location(x,y)int moveX, moveY; //X方向，Y方向移動大小。moveX = Cursor.Position.X - mouseDownPoint.X;moveY = Cursor.Position.Y - mouseDownPoint.Y;x = pictureBox1.Location.X + moveX;y = pictureBox1.Location.Y + moveY; pictureBox1.Location = new Point(x, y);mouseDownPoint.X = Cursor.Position.X;mouseDownPoint.Y = Cursor.Position.Y; }}private void panel2_MouseDown(object sender, MouseEventArgs e){if (e.Button == MouseButtons.Left){mouseDownPoint.X = Cursor.Position.X; //記錄鼠標左鍵按下時位置mouseDownPoint.Y = Cursor.Position.Y;isMove = true;}}private void panel2_MouseUp(object sender, MouseEventArgs e){if (e.Button == MouseButtons.Left){isMove = false;}}private void panel2_MouseMove(object sender, MouseEventArgs e){panel2.Focus(); //鼠標不在picturebox上時焦點給別的控件，此時無法縮放 if (isMove){int x, y; //新的pictureBox1.Location(x,y)int moveX, moveY; //X方向，Y方向移動大小。moveX = Cursor.Position.X - mouseDownPoint.X;moveY = Cursor.Position.Y - mouseDownPoint.Y;x = pictureBox1.Location.X + moveX;y = pictureBox1.Location.Y + moveY;pictureBox1.Location = new Point(x, y);mouseDownPoint.X = Cursor.Position.X;mouseDownPoint.Y = Cursor.Position.Y;}}2.圖像縮放核心思想：利用picturebox的zoom模式，根據圖像顯示大小更改picturebox大小，記錄鼠標位置補償縮放位移，實現錨點縮放，即以鼠標位置為中心進行縮放。

zoomstep --- 自己定義滾輪滑動縮放大小

代碼：//實現錨點縮放(以鼠標所指位置為中心縮放)；//步驟：//①先改picturebox長寬，長寬改變量一樣；//②獲取縮放后picturebox中實際顯示圖像的長寬，這里長寬是不一樣的；//③將picturebox的長寬設置為顯示圖像的長寬；//④補償picturebox因縮放產生的位移，實現錨點縮放。// 注釋：為啥要②③步？由于zoom模式的機制，把picturebox背景設為黑就知道為啥了。//這里需要獲取zoom模式下picturebox所顯示圖像的大小信息，添加 using System.Reflection；//pictureBox1_MouseWheel事件沒找到。。。手動添加，別忘在Form1.Designer.cs的“Windows 窗體設計器生成的代碼”里加入： //this.pictureBox1.MouseWheel += new System.Windows.Forms.MouseEventHandler(this.pictureBox1_MouseWheel)。private void pictureBox1_MouseWheel(object sender, MouseEventArgs e){int x = e.Location.X;int y = e.Location.Y;int ow = pictureBox1.Width;int oh = pictureBox1.Height; int VX, VY; //因縮放產生的位移矢量if (e.Delta > 0) //放大 {//第①步pictureBox1.Width += zoomStep; pictureBox1.Height += zoomStep;//第②步PropertyInfo pInfo = pictureBox1.GetType().GetProperty("ImageRectangle", BindingFlags.Instance |BindingFlags.NonPublic);Rectangle rect = (Rectangle)pInfo.GetValue(pictureBox1, null);//第③步pictureBox1.Width = rect.Width;pictureBox1.Height = rect.Height;}if (e.Delta < 0) //縮小 {//防止一直縮成負值if (pictureBox1.Width < myBmp.Width / 10)return;pictureBox1.Width -= zoomStep;pictureBox1.Height -= zoomStep;PropertyInfo pInfo = pictureBox1.GetType().GetProperty("ImageRectangle", BindingFlags.Instance |BindingFlags.NonPublic);Rectangle rect = (Rectangle)pInfo.GetValue(pictureBox1, null);pictureBox1.Width = rect.Width;pictureBox1.Height = rect.Height;}//第④步，求因縮放產生的位移，進行補償，實現錨點縮放的效果VX = (int)((double)x * (ow - pictureBox1.Width) / ow);VY = (int)((double)y * (oh - pictureBox1.Height) / oh);pictureBox1.Location = new Point(pictureBox1.Location.X + VX, pictureBox1.Location.Y + VY);}

總結

以上是生活随笔為你收集整理的c# picturebox 图像拖拽和缩放的全部內容，希望文章能夠幫你解決所遇到的問題。

如果覺得生活随笔網站內容還不錯，歡迎將生活随笔推薦給好友。