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using System;

/// <summary>

/// Summary description for Class1

/// </summary>

public class Class1

{

public Class1()

{

    }

    //找到点击点离要素最近的那个点（用于线边缘捕捉）

private IPoint ReturnNearestPoint(IFeatureClass t_pBaseFeatureClass,IPoint t_pInPoint)

{

 

  IFeatureClass pBaseFeatureClass=t_pBaseFeatureClass;

  IPoint pInPoint=t_pInPoint;

  IFeatureCursor pFeatureCursor;

  IFeature pFeature;

  IGeometry pGeometry;

  double dblDistance=10;//容差

  IProximityOperator pProximityOperator;

  IPoint pNearestPoint=null;

  //MessageBox.Show("return2");

  pFeatureCursor=pBaseFeatureClass.Search(null,false);

  pFeature=pFeatureCursor.NextFeature();

 

  while (pFeature!=null)

  {

   //MessageBox.Show("return4");

   pGeometry=pFeature.Shape;

   pProximityOperator=(IProximityOperator)pGeometry;

   if (dblDistance>pProximityOperator.ReturnDistance(pInPoint))

   {

    dblDistance=pProximityOperator.ReturnDistance(pInPoint);

    //MessageBox.Show("dblDistance");

    pNearestPoint=pProximityOperator.ReturnNearestPoint(pInPoint,esriSegmentExtension.esriNoExtension);

    //MessageBox.Show("pNearestPoint");

   }

   pFeature=pFeatureCursor.NextFeature();

  }

 

  return pNearestPoint;

}

    //打断线，用于在点击点处，打断该条线

    private void SplitePolylineByHitPoint(IFeatureClass t_pLineFeatureClass,IPoint t_pPoint)

{

 

  IFeatureClass pFeatureClass=t_pLineFeatureClass;

  IFeatureCursor pFeatureCursor;

  IFeature pFeature;

  pFeatureCursor=pFeatureClass.Search(null,false);

  pFeature=pFeatureCursor.NextFeature();

  IRelationalOperator  pRelationalOperator ;

  //遍历featureClass找到点中的那条线

  while (pFeature!=null)

  {

   pRelationalOperator=(IRelationalOperator)pFeature.Shape;

   bool bHasCrosses=pRelationalOperator.Contains(t_pPoint);

   if (bHasCrosses)

   {

    //对那条线在点击点处，进行打断

    IPolycurve pPolycurve=(IPolycurve)pFeature.Shape;

    bool HasSplitHappened ;

    int newPartIndex;

    int newSegmentIndex;

    //打断

    pPolycurve.SplitAtPoint(t_pPoint,false,true,out HasSplitHappened,out newPartIndex,out newSegmentIndex);

    if (HasSplitHappened)

    {

     //从GeometryCollection中分离出打断后的要素，并生成新的要素，并赋于属性

     IFeature pNewFeature;

     IGeometryCollection pGeometryCollection=(IGeometryCollection)pPolycurve;

     for (int i=0;i<pGeometryCollection.GeometryCount;i++)

     {

      //生成新的要素

      m_pWorkspaceEdit.StartEditing(false);

      m_pWorkspaceEdit.StartEditOperation();

      pNewFeature=pFeatureClass.CreateFeature();

      IGeometryCollection pline=new PolylineClass();

      IGeometry pGeo=pGeometryCollection.get_Geometry(i);

      pline.AddGeometries(1,ref pGeo);

      pNewFeature.Shape=(IPolyline)pline;

      pNewFeature.Store();

      m_pWorkspaceEdit.StopEditOperation();

      m_pWorkspaceEdit.StopEditing(true);

      IRow pRow =(IRow)pFeature;

      int intIndex=pRow.Fields.FindField("CRoadID");

      //进行属性复制

      for(int k=2;k<pRow.Fields.FieldCount-3;k++)//前后几个属性字段不添加

      {

       if (pRow.Fields.get_Field(k).Name=="Shape_Length")

       {

        continue;

       }

       if (k!=intIndex)

       {

       

        if (!pRow.get_Value(k).ToString().Equals(""))

        {

        

         pNewFeature.set_Value(k,pRow.get_Value(k));

        }

       }

       else

       {

        if (k==0)

        {

         if (!pRow.get_Value(k).ToString().Equals(""))

         {

          pNewFeature.set_Value(k,pRow.get_Value(k));

         }

        }

        else

        {

        

         if (!pRow.get_Value(k).ToString().Equals(""))

         {

          int intNO=System.Convert.ToInt32(pRow.get_Value(k).ToString())+1000*i;

          pNewFeature.set_Value(k,intNO);

         }

        }

       }

      }

      pNewFeature.Store();

     }

     pFeature.Delete();

    }

   }

   pFeature=pFeatureCursor.NextFeature();

  }

}

}