在C#中，要实现子窗口的拖拽和缩放功能，可以使用Windows Forms或WPF。这里分别给出两种方法的实现方法：
拖拽功能：
首先，需要在子窗口上添加一个Panel控件作为标题栏。然后，为该Panel添加MouseDown、MouseMove和MouseUp事件。
public partial class ChildForm : Form { public ChildForm() { InitializeComponent(); } private bool dragging = false; private Point dragCursorPoint; private Point dragFormPoint; private void panelTitleBar_MouseDown(object sender, MouseEventArgs e) { dragging = true; dragCursorPoint = Cursor.Position; dragFormPoint = this.Location; } private void panelTitleBar_MouseMove(object sender, MouseEventArgs e) { if (dragging) { Point dif = Point.Subtract(Cursor.Position, new Size(dragCursorPoint)); this.Location = Point.Add(dragFormPoint, new Size(dif)); } } private void panelTitleBar_MouseUp(object sender, MouseEventArgs e) { dragging = false; } } 缩放功能：
在子窗口的边缘添加一个透明的Panel控件作为缩放区域。然后，为该Panel添加MouseDown、MouseMove和MouseUp事件。
private bool resizing = false; private Point resizeCursorPoint; private Point resizeFormSize; private void panelResize_MouseDown(object sender, MouseEventArgs e) { resizing = true; resizeCursorPoint = Cursor.Position; resizeFormSize = this.Size; } private void panelResize_MouseMove(object sender, MouseEventArgs e) { if (resizing) { Point dif = Point.Subtract(Cursor.Position, new Size(resizeCursorPoint)); this.Size = new Size(resizeFormSize.Width + dif.X, resizeFormSize.Height + dif.Y); } } private void panelResize_MouseUp(object sender, MouseEventArgs e) { resizing = false; } 拖拽功能：
在子窗口的标题栏上添加鼠标事件。
<!-- 标题栏内容 --> </Border> private bool dragging = false; private Point dragStartPosition; private void titleBar_MouseLeftButtonDown(object sender, MouseButtonEventArgs e) { dragging = true; dragStartPosition = e.GetPosition(this); this.CaptureMouse(); } private void titleBar_MouseMove(object sender, MouseEventArgs e) { if (dragging) { Point currentPosition = e.GetPosition(this); double offsetX = currentPosition.X - dragStartPosition.X; double offsetY = currentPosition.Y - dragStartPosition.Y; this.Left += offsetX; this.Top += offsetY; } } protected override void OnMouseLeftButtonUp(MouseButtonEventArgs e) { base.OnMouseLeftButtonUp(e); dragging = false; this.ReleaseMouseCapture(); } 缩放功能：
在子窗口的边缘添加一个透明的Border控件作为缩放区域。然后，为该Border添加鼠标事件。
private bool resizing = false; private Point resizeStartPosition; private void resizeGrip_MouseLeftButtonDown(object sender, MouseButtonEventArgs e) { resizing = true; resizeStartPosition = e.GetPosition(this); this.CaptureMouse(); } private void resizeGrip_MouseMove(object sender, MouseEventArgs e) { if (resizing) { Point currentPosition = e.GetPosition(this); double offsetX = currentPosition.X - resizeStartPosition.X; double offsetY = currentPosition.Y - resizeStartPosition.Y; this.Width += offsetX; this.Height += offsetY; } } protected override void OnMouseLeftButtonUp(MouseButtonEventArgs e) { base.OnMouseLeftButtonUp(e); resizing = false; this.ReleaseMouseCapture(); } 这样就实现了子窗口的拖拽和缩放功能。
