Arcenginee鼠标控制框选一个区域
时间: 2023-08-30 22:12:28 浏览: 48
要在ArcEngine中使用鼠标控制框选一个区域,可以使用以下步骤:
1. 在地图上添加一个鼠标操作监听器。
2. 实现鼠标按下、移动和释放事件的处理方法,在鼠标按下时记录起始点,在鼠标移动时更新框选区域的位置和大小,在鼠标释放时完成框选操作。
3. 在地图上添加一个矩形元素,用于显示框选区域。
4. 在鼠标移动事件中更新矩形元素的位置和大小,以实时显示框选区域。
5. 在鼠标释放事件中根据框选区域的位置和大小进行要素选择或其他操作。
以下是一个简单的代码示例,演示如何使用鼠标控制框选一个区域:
```csharp
public class MyMapControl : AxMapControl
{
private IRectangleElement m_RectangleElement;
private IPoint m_StartPoint;
private bool m_IsDragging;
public MyMapControl()
{
this.OnMouseDown += new IMapControlEvents2_Ax_OnMouseDownEventHandler(MyMapControl_OnMouseDown);
this.OnMouseMove += new IMapControlEvents2_Ax_OnMouseMoveEventHandler(MyMapControl_OnMouseMove);
this.OnMouseUp += new IMapControlEvents2_Ax_OnMouseUpEventHandler(MyMapControl_OnMouseUp);
}
private void MyMapControl_OnMouseDown(object sender, IMapControlEvents2_OnMouseDownEvent e)
{
if (e.button == 1) // 左键按下
{
m_StartPoint = this.ToMapPoint(e.x, e.y);
m_RectangleElement = new RectangleElementClass();
m_RectangleElement.Geometry = new EnvelopeClass();
m_IsDragging = true;
}
}
private void MyMapControl_OnMouseMove(object sender, IMapControlEvents2_OnMouseMoveEvent e)
{
if (m_IsDragging)
{
IEnvelope envelope = m_RectangleElement.Geometry as IEnvelope;
envelope.XMin = Math.Min(m_StartPoint.X, e.mapX);
envelope.XMax = Math.Max(m_StartPoint.X, e.mapX);
envelope.YMin = Math.Min(m_StartPoint.Y, e.mapY);
envelope.YMax = Math.Max(m_StartPoint.Y, e.mapY);
this.ActiveView.PartialRefresh(esriViewDrawPhase.esriViewForeground, null, null);
}
}
private void MyMapControl_OnMouseUp(object sender, IMapControlEvents2_OnMouseUpEvent e)
{
if (m_IsDragging)
{
m_IsDragging = false;
IEnvelope envelope = m_RectangleElement.Geometry as IEnvelope;
if (envelope.Width > 0 && envelope.Height > 0)
{
// TODO: 根据框选区域进行要素选择或其他操作
}
m_RectangleElement = null;
this.ActiveView.PartialRefresh(esriViewDrawPhase.esriViewForeground, null, null);
}
}
protected override void OnPaint(PaintEventArgs e)
{
base.OnPaint(e);
if (m_IsDragging && m_RectangleElement != null)
{
IActiveView activeView = this.ActiveView;
IDisplay display = activeView.ScreenDisplay;
m_RectangleElement.Draw(display, null);
}
}
}
```