Implementing an XML builder external component
XMLDocImpl.cs
// Copyright 2010 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.Collections.Generic;
using System.Text;
using System.Runtime.InteropServices;
using ESRI.ArcGIS.Schematic;
using System.Windows.Forms;

namespace MyExtXmlComponentCS
{
  [Guid("0CE2EC0B-975A-4795-A7C2-EF31978D92A2")]
  [ClassInterface(ClassInterfaceType.None)]
  [ProgId("MyExtXmlComponentCS.XMLDocImpl")]
  public class XMLDocImpl : ISchematicXmlGenerate, ISchematicXmlUpdate
  {
    //
    #region Variables
    //This class must implement the ISchematicXMLGenerate and ISchematicXMLUpdate interfaces

    private ESRI.ArcGIS.ArcMap.Application m_application;         //ArcMap application
    private ESRI.ArcGIS.ArcMapUI.IMxDocument m_mxDocument;     //ArcMap document

    //The following arrays will be used to create the wished propertyset properties in the XML DOMDocument
    private string[] m_stationsPropertiesArray = { "Name", "Capacity", "Type", "Feeder" };
    private string[] m_feedersPropertiesArray = { "Feeder_Description" };
    private string[] m_LVLinesPropertiesArray = { "Rate", "Category" };
    private const string DatasetName = "ElectricDataSet";

    ~XMLDocImpl()
    {
      m_application = null;
      m_mxDocument = null; ;
    }
    #endregion

    #region ISchematicXmlGenerate Members

    public void GenerateXmlData(string diagramName, string diagramClassName, ref object xmlSource, ref bool cancel)
    {
      MSXML2.DOMDocument xmlDOMDocument = new MSXML2.DOMDocument();
      ESRI.ArcGIS.Carto.IMaps maps;
      ESRI.ArcGIS.Carto.IMap currentMap;
      ESRI.ArcGIS.Geodatabase.IEnumFeature enumFeature;
      ESRI.ArcGIS.Geodatabase.IFeature feature;
      MSXML2.IXMLDOMProcessingInstruction xmlProcInstr;
      MSXML2.IXMLDOMElement xmlDiagrams;
      MSXML2.IXMLDOMElement xmlDiagram;
      MSXML2.IXMLDOMElement xmlFeatures;
      MSXML2.IXMLDOMElement xmlDataSources;
      MSXML2.IXMLDOMElement xmlDataSource;
      MSXML2.IXMLDOMElement xmlDataSource_Namestring;
      MSXML2.IXMLDOMElement xmlDataSource_WorkspaceInfo;
      MSXML2.IXMLDOMElement xmlWorkspaceInfo_PathName;
      MSXML2.IXMLDOMElement xmlWorkspaceInfo_WorkspaceFactoryProgID;
      MSXML2.IXMLDOMAttribute rootAtt1;
      MSXML2.IXMLDOMAttribute rootAtt2;
      ESRI.ArcGIS.Geodatabase.IEnumFeatureSetup enumFeatureSetup;
      string xmlDatabase;

      // Retrieving the selected set of features
      enumFeature = null;
      feature = null;

      m_mxDocument = (ESRI.ArcGIS.ArcMapUI.IMxDocument)m_application.Document;
      maps = m_mxDocument.Maps;
      int i = 0;
      while (i < maps.Count)
      {
        currentMap = maps.get_Item(i);
        enumFeature = (ESRI.ArcGIS.Geodatabase.IEnumFeature)currentMap.FeatureSelection;
        enumFeatureSetup = (ESRI.ArcGIS.Geodatabase.IEnumFeatureSetup)enumFeature;
        enumFeatureSetup.AllFields = true;
        feature = enumFeature.Next();
        if (feature != null) break;

        i += 1;
      }

      // if (there is no selected feature in the MxDocument, the procedure is interrupted
      if (feature == null)
      {
        MessageBox.Show("There is no feature selected. Select a set of features.", "Generate/Update XML diagrams", MessageBoxButtons.OK, MessageBoxIcon.Exclamation);
        cancel = true;
        return;
      }

      //Checking the feature dataset related to the selected features
      ESRI.ArcGIS.Geodatabase.IFeatureClass featureClass;
      string featureDatasetName;
      featureClass = (ESRI.ArcGIS.Geodatabase.IFeatureClass)feature.Class;
      featureDatasetName = featureClass.FeatureDataset.BrowseName;
      xmlDatabase = featureClass.FeatureDataset.Workspace.PathName;

      // if the selected features come from another feature dataset than the expected one, the procedure is interrupted
      if (featureDatasetName != DatasetName)
      {
        //More restrictive condition: if (xmlDatabase != "c:\Mybase.gdb" ) 
        MessageBox.Show("This component doesn't work from the selected set of features.");
        cancel = true;
        return;
      }

      // Writing the XML heading items in the DOMDocument
      xmlProcInstr = xmlDOMDocument.createProcessingInstruction("xml", "version='1.0'");
      xmlDOMDocument.appendChild(xmlProcInstr);
      xmlProcInstr = null;

      //-------- Diagrams Section START --------
      // Creating the root Diagrams element
      xmlDiagrams = xmlDOMDocument.createElement("Diagrams");
      xmlDOMDocument.documentElement = xmlDiagrams;
      rootAtt1 = xmlDOMDocument.createAttribute("xmlns:xsi");
      rootAtt1.text = "http://www.w3.org/2001/XMLSchema-instance";
      xmlDiagrams.attributes.setNamedItem(rootAtt1);

      // Creating the Diagram element for the diagram which is going to be generated
      xmlDiagram = xmlDOMDocument.createElement("Diagram");
      xmlDiagrams.appendChild(xmlDiagram);
      rootAtt1 = xmlDOMDocument.createAttribute("EnforceDiagramTemplateName");
      rootAtt1.text = "false";
      xmlDiagram.attributes.setNamedItem(rootAtt1);
      rootAtt2 = xmlDOMDocument.createAttribute("EnforceDiagramName");
      rootAtt2.text = "false";
      xmlDiagram.attributes.setNamedItem(rootAtt2);

      //-------- DataSources Section START --------
      // Creating the DataSources element 
      xmlDataSources = xmlDOMDocument.createElement("Datasources");
      xmlDiagram.appendChild(xmlDataSources);
      xmlDataSource = xmlDOMDocument.createElement("Datasource");
      xmlDataSources.appendChild(xmlDataSource);

      // Specifying the Namestring for the related Datasource element
      xmlDataSource_Namestring = xmlDOMDocument.createElement("NameString");
      xmlDataSource.appendChild(xmlDataSource_Namestring);
      xmlDataSource_Namestring.nodeTypedValue = "XMLDataSource";

      // Specifying the WorkspaceInfo for the related Datasource element
      xmlDataSource_WorkspaceInfo = xmlDOMDocument.createElement("WorkSpaceInfo");
      xmlDataSource.appendChild(xmlDataSource_WorkspaceInfo);
      xmlWorkspaceInfo_PathName = xmlDOMDocument.createElement("PathName");
      xmlDataSource_WorkspaceInfo.appendChild(xmlWorkspaceInfo_PathName);
      xmlWorkspaceInfo_PathName.nodeTypedValue = xmlDatabase;
      xmlWorkspaceInfo_WorkspaceFactoryProgID = xmlDOMDocument.createElement("WorkspaceFactoryProgID");
      xmlDataSource_WorkspaceInfo.appendChild(xmlWorkspaceInfo_WorkspaceFactoryProgID);
      xmlWorkspaceInfo_WorkspaceFactoryProgID.nodeTypedValue = "esriDataSourcesGDB.FileGDBWorkspaceFactory";
      //-------- DataSources Section END --------

      //-------- Features Section START --------
      xmlFeatures = xmlDOMDocument.createElement("Features");
      xmlDiagram.appendChild(xmlFeatures);
      while (feature != null)
      {
        switch (feature.FeatureType)
        {
          case ESRI.ArcGIS.Geodatabase.esriFeatureType.esriFTSimpleJunction:
            CreateXMLNodeElt(feature, ref xmlDOMDocument, ref xmlFeatures, feature.Class.AliasName);
            break;
          case ESRI.ArcGIS.Geodatabase.esriFeatureType.esriFTSimpleEdge:
            CreateXMLLinkElt(feature, ref xmlDOMDocument, ref xmlFeatures, feature.Class.AliasName);
            break;
        }
        feature = enumFeature.Next();

      }

      // output the XML we created
      xmlSource = xmlDOMDocument;
      cancel = false;
      //-------- Features Section END --------
      //-------- Diagrams Section END --------

    }


    #endregion

    #region ISchematicXmlUpdate Members

    public void UpdateXmlData(string diagramName, string diagramClassName, string updateInformation, ref    object xmlSource, ref  bool cancel)
    {
      GenerateXmlData(diagramName, diagramClassName, ref xmlSource, ref  cancel);
    }

    #endregion

    #region "private functions"
    // The following CreateXMLLNodeElt private procedure is used to create all the expected 
    // XML items for a XML NodeFeature related to a Station or Feeder simple junction feature
    private void CreateXMLNodeElt(ESRI.ArcGIS.Geodatabase.IFeature inFeature, ref MSXML2.DOMDocument outDOMDoc, ref MSXML2.IXMLDOMElement outXMLElements, string inNodeTypeName)
    {

      if (!inFeature.HasOID)
      {
        MessageBox.Show("No OID");
        return;
      }

      MSXML2.IXMLDOMElement xmlNode;
      MSXML2.IXMLDOMElement xmlNode_XCoord;
      MSXML2.IXMLDOMElement xmlNode_YCoord;
      MSXML2.IXMLDOMElement xmlNode_RelatedContainerID;
      bool relatedContainer;
      MSXML2.IXMLDOMNodeList xmlNodeList;
      MSXML2.IXMLDOMElement xmlDrawing;
      MSXML2.IXMLDOMElement xmlDrawing_EltTypeName;
      MSXML2.IXMLDOMElement xmlDrawing_ExternalUID;

      //-------- Feature Section START related to the "infeature" --------
      // Creating the NodeFeature element
      xmlNode = outDOMDoc.createElement("NodeFeature");
      outXMLElements.appendChild(xmlNode);
      // Specifying basic XML items for this NodeFeature
      CreateBasicXMLItemsForSchematicElt(inFeature, ref outDOMDoc, ref xmlNode, inNodeTypeName);

      // Specifying its X && Y when they exist
      if ((inFeature.Fields.FindField("X") > 0) && (inFeature.Fields.FindField("Y") > 0))
      {
        // Specifying InitialX
        xmlNode_XCoord = outDOMDoc.createElement("InitialX");
        xmlNode.appendChild(xmlNode_XCoord);
        xmlNode_XCoord.nodeTypedValue = inFeature.get_Value(inFeature.Fields.FindField("X"));
        // Specifying InitialY
        xmlNode_YCoord = outDOMDoc.createElement("InitialY");
        xmlNode.appendChild(xmlNode_YCoord);
        xmlNode_YCoord.nodeTypedValue = inFeature.get_Value(inFeature.Fields.FindField("Y"));
      }

      xmlNode_RelatedContainerID = outDOMDoc.createElement("RelatedContainerID");
      xmlNode.appendChild(xmlNode_RelatedContainerID);

      // Specifying its properties 
      switch (inFeature.Class.AliasName)
      {
        case "Station":
          {
            xmlNode_RelatedContainerID.nodeTypedValue = "Container-" + System.Convert.ToString(inFeature.get_Value(inFeature.Fields.FindField("Feeder")));
            // For Station feature, the field contained in the StationsPropertiesArray will be exported
            CompleteXMLEltByProperties(inFeature, ref outDOMDoc, ref xmlNode, m_stationsPropertiesArray);
            break;
          }
        case "Feeder":
          {
            xmlNode_RelatedContainerID.nodeTypedValue = "Container-" + inFeature.OID.ToString();
            // For Feeder feature, the field contained in the StationsPropertiesArray will be exported          
            CompleteXMLEltByProperties(inFeature, ref outDOMDoc, ref xmlNode, m_feedersPropertiesArray);
            break;
          }
      }
      //-------- Feature Section END related to the "infeature" --------

      // Checking the existence of the related container 
      xmlNodeList = outXMLElements.selectNodes("NodeFeature/ExternalUniqueID");
      relatedContainer = false;

      foreach (MSXML2.IXMLDOMNode node in xmlNodeList)
      {
        if (node.text == xmlNode_RelatedContainerID.nodeTypedValue.ToString())
        {
          relatedContainer = true;
          break;
        }
      } // pNode

      // Creating the related container when it doesn//t already exist
      if (!relatedContainer)
      {
        xmlDrawing = outDOMDoc.createElement("NodeFeature");
        outXMLElements.appendChild(xmlDrawing);
        // Specifying its FeatureClassName
        xmlDrawing_EltTypeName = outDOMDoc.createElement("FeatureClassName");
        xmlDrawing.appendChild(xmlDrawing_EltTypeName);
        xmlDrawing_EltTypeName.nodeTypedValue = "Containers";
        // Specifying its ExternalUniqueID
        xmlDrawing_ExternalUID = outDOMDoc.createElement("ExternalUniqueID");
        xmlDrawing.appendChild(xmlDrawing_ExternalUID);
        xmlDrawing_ExternalUID.nodeTypedValue = xmlNode_RelatedContainerID.nodeTypedValue;
      }
    }

    // The following CreateXMLLinkElt private procedure is used to create all the expected XML items for a XML LinkFeature related to a HV_Line or LV_Line simple edge feature
    private void CreateXMLLinkElt(ESRI.ArcGIS.Geodatabase.IFeature inFeature, ref MSXML2.DOMDocument outDOMDoc, ref MSXML2.IXMLDOMElement outXMLElements, string inLinkTypeName)
    {
      if (!inFeature.HasOID)
      {
        MessageBox.Show("No OID");
        return;
      }

      MSXML2.IXMLDOMElement xmlLink;
      MSXML2.IXMLDOMElement xmlLink_FromNode;
      MSXML2.IXMLDOMElement xmlLink_ToNode;
      int indexListPoints;
      string listPoints;
      int nbVertices;
      string vertices;
      MSXML2.IXMLDOMElement xmlLink_Vertices;
      MSXML2.IXMLDOMElement xmlLink_Vertex;
      MSXML2.IXMLDOMElement xmlLink_XVertex;
      MSXML2.IXMLDOMElement xmlLink_YVertex;
      string xValue;
      string yValue;

      //-------- Feature Section START related to the "infeature" --------
      // Creating the LinkFeature Feature
      xmlLink = outDOMDoc.createElement("LinkFeature");
      outXMLElements.appendChild(xmlLink);

      // Specifying basic XML items for this LinkFeature
      CreateBasicXMLItemsForSchematicElt(inFeature, ref outDOMDoc, ref xmlLink, inLinkTypeName);
      // Specifying its FromNode
      xmlLink_FromNode = outDOMDoc.createElement("FromNode");
      xmlLink.appendChild(xmlLink_FromNode);
      xmlLink_FromNode.nodeTypedValue = inFeature.get_Value(inFeature.Fields.FindField("FromJunctionType")) + "-" + inFeature.get_Value(inFeature.Fields.FindField("FromJunctionOID"));
      // Specifying its ToNode
      xmlLink_ToNode = outDOMDoc.createElement("ToNode");
      xmlLink.appendChild(xmlLink_ToNode);
      xmlLink_ToNode.nodeTypedValue = inFeature.get_Value(inFeature.Fields.FindField("ToJunctionType")) + "-" + inFeature.get_Value(inFeature.Fields.FindField("ToJunctionOID"));

      //Add Vertices to LinkFeature ---- NEED TO BE COMPLETED
      indexListPoints = inFeature.Fields.FindField("ListPoints");
      if (indexListPoints > 0)
      {
        listPoints = "";
        listPoints = inFeature.get_Value(indexListPoints).ToString();
        if (listPoints != "")
        {
          int foundChar = listPoints.IndexOf(";", 1);
          nbVertices = System.Convert.ToInt32(listPoints.Substring(0, foundChar));
          vertices = listPoints.Substring(foundChar + 1);
          if (nbVertices > 0)
          {
            // Specifying its Vertices
            xmlLink_Vertices = outDOMDoc.createElement("Vertices");
            xmlLink.appendChild(xmlLink_Vertices);

            int iLoc;
            for (int i = 1; i <= nbVertices; i++)
            {
              xValue = "";
              yValue = "";
              iLoc = vertices.IndexOf(";", 1);
              if (vertices != "" && (iLoc) > 0)
              {
                xValue = vertices.Substring(0, iLoc);
              }
              vertices = vertices.Substring(iLoc + 1);
              iLoc = vertices.IndexOf(";", 1);
              if (vertices != ";" && (iLoc) > 0)
              {
                yValue = vertices.Substring(0, iLoc);
              }

              if (xValue != "" && yValue != "")
              {
                xmlLink_Vertex = outDOMDoc.createElement("Vertex");
                xmlLink_Vertices.appendChild(xmlLink_Vertex);
                xmlLink_XVertex = outDOMDoc.createElement("X");
                xmlLink_Vertex.appendChild(xmlLink_XVertex);
                xmlLink_XVertex.nodeTypedValue = xValue;
                xmlLink_YVertex = outDOMDoc.createElement("Y");
                xmlLink_Vertex.appendChild(xmlLink_YVertex);
                xmlLink_YVertex.nodeTypedValue = yValue;
                if (vertices.Length - iLoc > 0)
                {
                  vertices = vertices.Substring(iLoc + 1); //sVertices.Length - iLoc)
                }
                else
                {
                  break;
                }
              }
              else
              {
                break;
              }
            }
          }
        }

        //Specifying its properties
        switch (inFeature.Class.AliasName)
        {
          case "LV_Line":
            {
              CompleteXMLEltByProperties(inFeature, ref outDOMDoc, ref  xmlLink, m_LVLinesPropertiesArray);
              break;
            }
        }
        //-------- Feature Section END related to the "infeature" --------
      }
    }


    // The following CreateBasicXMLItmesForSchematicElt private procedure is used to create the first expected XML items for a XML NodeFeature or LinkFeature
    private void CreateBasicXMLItemsForSchematicElt(ESRI.ArcGIS.Geodatabase.IFeature inFeature,
                                                    ref MSXML2.DOMDocument outDOMDoc,
                                                    ref MSXML2.IXMLDOMElement outXMLElement,
                                                    string inEltTypeName)
    {
      MSXML2.IXMLDOMElement xmlElt_EltTypeName;
      MSXML2.IXMLDOMElement xmlElt_ExternalUID;
      MSXML2.IXMLDOMElement xmlElt_DatasourceName;
      MSXML2.IXMLDOMElement xmlElt_UCID;
      MSXML2.IXMLDOMElement xmlElt_UOID;

      // Specifying its FeatureClassName
      xmlElt_EltTypeName = outDOMDoc.createElement("FeatureClassName");
      outXMLElement.appendChild(xmlElt_EltTypeName);
      if (inFeature.Fields.FindField("Feeder") != -1)
      {
        xmlElt_EltTypeName.nodeTypedValue = inEltTypeName + "sFeeder" + inFeature.get_Value(inFeature.Fields.FindField("Feeder")).ToString();
      }
      else
      {
        xmlElt_EltTypeName.nodeTypedValue = inEltTypeName + "s";
      }

      // Specifying its ExternalUniqueID
      xmlElt_ExternalUID = outDOMDoc.createElement("ExternalUniqueID");
      outXMLElement.appendChild(xmlElt_ExternalUID);
      xmlElt_ExternalUID.nodeTypedValue = inEltTypeName + "-" + inFeature.OID.ToString();

      // Specifying its DatasourceName
      xmlElt_DatasourceName = outDOMDoc.createElement("DatasourceName");
      outXMLElement.appendChild(xmlElt_DatasourceName);
      xmlElt_DatasourceName.nodeTypedValue = "XMLDataSource";

      // Specifying its UCID
      xmlElt_UCID = outDOMDoc.createElement("UCID");
      outXMLElement.appendChild(xmlElt_UCID);
      xmlElt_UCID.nodeTypedValue = inFeature.Class.ObjectClassID;

      // Add UOID to NodeElement
      xmlElt_UOID = outDOMDoc.createElement("UOID");
      outXMLElement.appendChild(xmlElt_UOID);
      xmlElt_UOID.nodeTypedValue = inFeature.OID;
    }

    // The following CompleteXMLEltByProperties private procedure is used to create all the expected propertyset properties listed in the input PropertiesArray array
    private void CompleteXMLEltByProperties(ESRI.ArcGIS.Geodatabase.IFeature inFeature,
                                            ref MSXML2.DOMDocument outDOMDoc,
                                            ref MSXML2.IXMLDOMElement outXMLElement,
                                            string[] propertiesArray)
    {
      int i = 0;
      MSXML2.IXMLDOMElement xmlPropertySet;
      MSXML2.IXMLDOMElement xmlPropertyArray;
      MSXML2.IXMLDOMElement xmlPropertySetProperty;
      MSXML2.IXMLDOMElement xmlProperty_Key;
      MSXML2.IXMLDOMElement xmlProperty_Value;

      if (propertiesArray.Length > 0)
      {
        //-------- PropertySet Section START --------
        // Creating the PropertySet element for the input outXMLElement
        xmlPropertySet = outDOMDoc.createElement("PropertySet");
        outXMLElement.appendChild(xmlPropertySet);
        // Creating the PropertyArray element
        xmlPropertyArray = outDOMDoc.createElement("PropertyArray");
        xmlPropertySet.appendChild(xmlPropertyArray);

        while (i < propertiesArray.Length)
        {
          // Creating the i PropertySetProperty
          xmlPropertySetProperty = outDOMDoc.createElement("PropertySetProperty");
          xmlPropertyArray.appendChild(xmlPropertySetProperty);
          // Specifying the key && value field related to that i PropertySetProperty
          xmlProperty_Key = outDOMDoc.createElement("Key");
          xmlPropertySetProperty.appendChild(xmlProperty_Key);
          xmlProperty_Key.nodeTypedValue = propertiesArray[i].ToString();
          xmlProperty_Value = outDOMDoc.createElement("Value");
          xmlPropertySetProperty.appendChild(xmlProperty_Value);
          xmlProperty_Value.nodeTypedValue = inFeature.get_Value(inFeature.Fields.FindField(propertiesArray[i].ToString()));
          i += 1;
        }
      }
      //-------- PropertySet Section END --------
    }
    #endregion

    public object ApplicationHook
    {
      get
      {
        return (object)m_application;
      }
      set
      {
        m_application = (ESRI.ArcGIS.ArcMap.Application)value;
      }
    }

  }
}