节点捕捉

// Copyright 2012 ESRI
// 
// All rights reserved under the copyright laws of the United States
// and applicable international laws, treaties, and conventions.
// 
// You may freely redistribute and use this sample code, with or
// without modification, provided you include the original copyright
// notice and use restrictions.
// 
// See the use restrictions.
// 

using System;
using System.Collections;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;

using ESRI.ArcGIS.Controls;
using ESRI.ArcGIS.esriSystem;
using ESRI.ArcGIS.Geodatabase;
using ESRI.ArcGIS.Geometry;
using ESRI.ArcGIS.Carto;
using ESRI.ArcGIS.Display;
using ESRI.ArcGIS.SystemUI;
using ESRI.ArcGIS.ADF.CATIDs;

namespace Core
{
  public partial class SnapEditor : Form
  {
    IEngineEditor editor;
    IEngineEditLayers editLayers;
    IEngineSnapEnvironment snapEnvironment;
       
    public SnapEditor()
    {
      InitializeComponent();

      //get the snapEnvironment
      editor = new EngineEditorClass();
      editLayers = editor as IEngineEditLayers;
      snapEnvironment = editor as IEngineSnapEnvironment;    
  
      //Update this form with the snap environment and snap tips
      //Note: from here on we expect all snap changes to be made via this form, so it is not updated after direct changes to the snapping 
      //environment or the Arc Engine Snap Window. 
      RefreshDisplay();
    }

    /// <summary>
    /// Update the window with the current snap environment and snap tip settings
    /// </summary>
    private void RefreshDisplay()
    {
      snapTolerance.Text = snapEnvironment.SnapTolerance.ToString();
      snapTolUnits.SelectedIndex = (int)snapEnvironment.SnapToleranceUnits;      
      snapTips.Checked = ((IEngineEditProperties2)editor).SnapTips;
      
      //remove all feature snap agents from the data grid view
      snapAgents.Rows.Clear();
               
      //display feature snap and snap agents that are active
      for (int i = 0; i < snapEnvironment.SnapAgentCount; i++)
      {
        try
        {
          IEngineSnapAgent snapAgent = snapEnvironment.get_SnapAgent(i);
          IEngineFeatureSnapAgent ftrSnapAgent = snapAgent as IEngineFeatureSnapAgent;

          if (ftrSnapAgent != null)
          {
            //for feature snap agents add a row to the data view grid 
            esriGeometryHitPartType hitType = ftrSnapAgent.HitType;
            bool vertex, edge, end;
            vertex = (hitType & esriGeometryHitPartType.esriGeometryPartVertex) == esriGeometryHitPartType.esriGeometryPartVertex;
            edge = (hitType & esriGeometryHitPartType.esriGeometryPartBoundary) == esriGeometryHitPartType.esriGeometryPartBoundary;
            end = (hitType & esriGeometryHitPartType.esriGeometryPartEndpoint) == esriGeometryHitPartType.esriGeometryPartEndpoint;
            string vertexString = vertex ? "vertex" : "      ";
            string edgeString = edge ? " edge" : "     ";
            string endString = end ? " end  " : "     ";
            string hitTypes = vertexString + edgeString + endString;
            object[] rowData = { snapAgent.Name.ToString(), ftrSnapAgent.FeatureClass.AliasName, hitTypes };
            snapAgents.Rows.Add(rowData);
          }
          else
          {
            //add the active edit sketch snap agents    
            object[] rowData = { snapAgent.Name.ToString(), "<not applicable>", "<not applicable>" };
            snapAgents.Rows.Add(rowData);
          }
        }
        catch (Exception)
        {
        }

      }
    }

    #region Button Handlers
    private void clearAgents_Click(object sender, EventArgs e)
    {
      snapEnvironment.ClearSnapAgents();
            
      //refresh this window
      RefreshDisplay();
    }

    /// <summary>
    /// Turns off feature snap agents and turns off edit sketch snap agents by removing them
    /// </summary>
    /// <remarks>
    /// Using Clear or Remove feature snap agents can be deactivated so that the user can't enable them.
    /// Here we simply turn off all the agents, which will allow the user to turn them on.
    /// </remarks>   
    private void turnOffAgents_Click(object sender, EventArgs e)
    {
      TurnOffAgents();       
    }
    
    private void reverseAgentsPriority_Click(object sender, EventArgs e)
    {
      //get all the snap agents in reverse order and then deactivate them
      ArrayList snapAgentList = new ArrayList();

      for (int i = snapEnvironment.SnapAgentCount - 1; i >= 0; i--)
      {
        IEngineSnapAgent tmpAgent = snapEnvironment.get_SnapAgent(i);
        snapAgentList.Add(tmpAgent);
        snapEnvironment.RemoveSnapAgent(i);
      }

      //add the agents back to the environment
      foreach (IEngineSnapAgent agent in snapAgentList)
      {
        snapEnvironment.AddSnapAgent(agent);
      }

      //refresh this window
      RefreshDisplay();
    }  

    /// <summary>
    /// Adds a feature snap agent for the target layer and turn on  all options.
    /// </summary>
    /// <remarks>
    /// This method does not check if there already exists a feature snap agent for the 
    /// target layer. It is recommended that you do so since duplicate agents can appear
    /// on the Snap Settings Form
    /// </remarks>    
    private void addFeatureSnapAgent_Click(object sender, EventArgs e)
    {
      IEngineFeatureSnapAgent featureSnapAgent = new EngineFeatureSnap();
      
      if (editLayers.TargetLayer == null)
      {
        System.Windows.Forms.MessageBox.Show("Please start an edit session");
        return;
      }
      
      featureSnapAgent.FeatureClass = editLayers.TargetLayer.FeatureClass; ;
      featureSnapAgent.HitType = esriGeometryHitPartType.esriGeometryPartVertex | esriGeometryHitPartType.esriGeometryPartBoundary | esriGeometryHitPartType.esriGeometryPartEndpoint;
      snapEnvironment.AddSnapAgent(featureSnapAgent); 
     
      //refresh this window
      RefreshDisplay();
    }

    /// <summary>
    /// Adds, and hence turns on, Edit Sketch snap agents
    /// </summary>
    private void addSketchSnapAgent_Click(object sender, EventArgs e)
    {
      AddSketchSnapAgents();
      RefreshDisplay();
    }  
    #endregion

    #region Snap Tips and Tolerance Handlers
    private void snapTips_CheckedChanged(object sender, EventArgs e)
    {
      try
      {
        //turn snap tips on/off      
        ((IEngineEditProperties2)editor).SnapTips = snapTips.Checked;
      }
      catch
      {
        snapTips.Checked = ((IEngineEditProperties2)editor).SnapTips;
      }
    }
       
    private void snapTolerance_TypeValidationEventHandler(object sender, TypeValidationEventArgs e)
    {
      try
      {
        snapEnvironment.SnapTolerance = Convert.ToDouble(snapTolerance.Text);
      }
      catch
      {
        snapTolerance.Text = snapEnvironment.SnapTolerance.ToString();
      }      
    }

    private void snapTolUnits_SelectedIndexChanged(object sender, EventArgs e)
    {
      try
      {
        snapEnvironment.SnapToleranceUnits = (esriEngineSnapToleranceUnits)snapTolUnits.SelectedIndex;
      }
      catch
      {
        snapTolUnits.SelectedIndex = (int)snapEnvironment.SnapToleranceUnits;
      }
    }
    #endregion
            
    #region Helper Methods
    /// <summary>
    /// Adds, and hence turns on, Edit Sketch snap agents
    /// </summary>
    private void AddSketchSnapAgents()
    {
      //give anchor snap (i.e. vertex snap) priority to get more accurate snap tips while snapped to a vertex
      Type t = Type.GetTypeFromProgID("esriControls.EngineAnchorSnap");
      System.Object obj = Activator.CreateInstance(t);
      IEngineSnapAgent snapAgent = (IEngineSnapAgent)obj;
      snapEnvironment.AddSnapAgent(snapAgent);

      //edge sketch edges
      t = Type.GetTypeFromProgID("esriControls.EngineSketchSnap");
      obj = Activator.CreateInstance(t);
      snapAgent = (IEngineSnapAgent)obj;
      snapEnvironment.AddSnapAgent(snapAgent);

      //perpendicular to edit sketch
      t = Type.GetTypeFromProgID("esriControls.EnginePerpendicularSnap");
      obj = Activator.CreateInstance(t);
      snapAgent = (IEngineSnapAgent)obj;
      snapEnvironment.AddSnapAgent(snapAgent);
    }

    /// <summary>
    /// Turns off feature snap agents and turns off edit sketch snap agents by removing them
    /// </summary>
    /// <remarks>
    /// Using Clear or Remove feature snap agents can be deactivated so that the user can't enable them.
    /// Here we simply turn off all the agents, which will allow the user to turn them on.
    /// </remarks>   
    private void TurnOffAgents()
    {
      for (int i = snapEnvironment.SnapAgentCount - 1; i >= 0; i--)
      {
        IEngineSnapAgent snapAgent = snapEnvironment.get_SnapAgent(i);
        IEngineFeatureSnapAgent ftrSnapAgent = snapAgent as IEngineFeatureSnapAgent;
        if (ftrSnapAgent != null)
        {
          //turn off the feature snap agent
          ftrSnapAgent.HitType = esriGeometryHitPartType.esriGeometryPartNone;
        }
        else
        {
          //there is no way to turn snap agents off, they must be removed 
          snapEnvironment.RemoveSnapAgent(i);
        }
      }

      //refresh this window
      RefreshDisplay();
    }
    #endregion
  }
}