ArcGIS Pro 3.4 API Reference Guide
ArcGIS.Core.Data.Knowledge Namespace / KnowledgeGraphObjectValue Class / GetKeys Method
Example Version

GetKeys Method (KnowledgeGraphObjectValue)
Gets the set of keys associated with the graph object value. This method must be called on the MCT. Use QueuedTask.Run.
Syntax
public virtual IReadOnlyList<string> GetKeys()

Return Value

Exceptions
ExceptionDescription
This method or property must be called within the lambda passed to QueuedTask.Run.
Example
Process a KnowledgeGraphRow Value
//Base class for entities and relationships
//(including documents and provenance)
public void ProcessGraphNamedObjectValue(
  KnowledgeGraphNamedObjectValue kg_named_obj_val)
{
  if (kg_named_obj_val is KnowledgeGraphEntityValue kg_entity)
  {
    var label = kg_entity.GetLabel();
    //TODO - use label
  }
  else if (kg_named_obj_val is KnowledgeGraphRelationshipValue kg_rel)
  {
    var has_entity_ids = kg_rel.GetHasRelatedEntityIDs();
    if (kg_rel.GetHasRelatedEntityIDs())
    {
      var origin_id = kg_rel.GetOriginID();
      var dest_id = kg_rel.GetDestinationID();
      //TODO - use ids
    }
  }
  var id = kg_named_obj_val.GetID();
  var oid = kg_named_obj_val.GetObjectID();
  //Note: Typename corresponds to the name of the feature class or table
  //in the relational gdb model -and- to the name of the KnowledgeGraphNamedObjectType
  //in the knowledge graph data model
  var type_name = kg_named_obj_val.GetTypeName();
  //TODO use id, object id, etc.
}

//Object values include entities, relationships, and anonymous objects
public void ProcessGraphObjectValue(KnowledgeGraphObjectValue kg_obj_val)
{
  switch (kg_obj_val)
  {
    case KnowledgeGraphEntityValue kg_entity:
      ProcessGraphNamedObjectValue(kg_entity);
      break;
    case KnowledgeGraphRelationshipValue kg_rel:
      ProcessGraphNamedObjectValue(kg_rel);
      break;
    default:
      //Anonymous objects
      break;
  }
  //graph object values have a set of properties (equivalent
  //to a collection of key/value pairs)
  var keys = kg_obj_val.GetKeys();
  foreach (var key in keys)
    ProcessKnowledgeGraphRowValue(kg_obj_val[key]);//Recurse
}

//Process a KnowledgeGraphValue from a query or search
public void ProcessGraphValue(KnowledgeGraphValue kg_val)
{
  switch (kg_val)
  {
    case KnowledgeGraphPrimitiveValue kg_prim:
      //KnowledgeGraphPrimitiveValue not currently used in
      //query and search 
      ProcessKnowledgeGraphRowValue(kg_prim.GetValue());//Recurse
      return;
    case KnowledgeGraphArrayValue kg_array:
      var count = kg_array.GetSize();
      //Recursively process each value in the array
      for (ulong i = 0; i < count; i++)
        ProcessKnowledgeGraphRowValue(kg_array[i]);//Recurse
      return;
    case KnowledgeGraphPathValue kg_path:
      //Entities
      var entity_count = kg_path.GetEntityCount();
      //Recursively process each entity value in the path
      for (ulong i = 0; i < entity_count; i++)
        ProcessGraphObjectValue(kg_path.GetEntity(i));//Recurse

      //Recursively process each relationship value in the path
      var relate_count = kg_path.GetRelationshipCount();
      for (ulong i = 0; i < relate_count; i++)
        ProcessGraphObjectValue(kg_path.GetRelationship(i));//Recurse
      return;
    case KnowledgeGraphObjectValue kg_object:
      ProcessGraphObjectValue(kg_object);//Recurse
      return;
    default:
      var type_string = kg_val.GetType().ToString();
      System.Diagnostics.Debug.WriteLine(
        $"Unknown: '{type_string}'");
      return;
  }
}

//Process each value from the KnowledgeGraphRow array
public void ProcessKnowledgeGraphRowValue(object value)
{
  switch (value)
  {
    //Graph value?
    case KnowledgeGraphValue kg_val:
      var kg_type = kg_val.KnowledgeGraphValueType.ToString();
      System.Diagnostics.Debug.WriteLine(
        $"KnowledgeGraphValue: '{kg_type}'");
      ProcessGraphValue(kg_val);//Recurse
      return;
    //Primitive types...add additional logic as needed
    case System.DBNull dbn:
      System.Diagnostics.Debug.WriteLine("DBNull.Value");
      return;
    case string str:
      System.Diagnostics.Debug.WriteLine($"'{str}' (string)");
      return;
    case long l_val:
      System.Diagnostics.Debug.WriteLine($"{l_val} (long)");
      return;
    case int i_val:
      System.Diagnostics.Debug.WriteLine($"{i_val} (int)");
      return;
    case short s_val:
      System.Diagnostics.Debug.WriteLine($"{s_val} (short)");
      return;
    case double d_val:
      System.Diagnostics.Debug.WriteLine($"{d_val} (double)");
      return;
    case float f_val:
      System.Diagnostics.Debug.WriteLine($"{f_val} (float)");
      return;
    case DateTime dt_val:
      System.Diagnostics.Debug.WriteLine($"{dt_val} (DateTime)");
      return;
    case DateOnly dt_only_val:
      System.Diagnostics.Debug.WriteLine($"{dt_only_val} (DateOnly)");
      return;
    case TimeOnly tm_only_val:
      System.Diagnostics.Debug.WriteLine($"{tm_only_val} (TimeOnly)");
      return;
    case DateTimeOffset dt_tm_offset_val:
      System.Diagnostics.Debug.WriteLine(
        $"{dt_tm_offset_val} (DateTimeOffset)");
      return;
    case System.Guid guid_val:
      var guid_string = guid_val.ToString("B");
      System.Diagnostics.Debug.WriteLine($"'{guid_string}' (Guid)");
      return;
    case Geometry geom_val:
      var geom_type = geom_val.GeometryType.ToString();
      var is_empty = geom_val.IsEmpty;
      var wkid = geom_val.SpatialReference?.Wkid ?? 0;
      System.Diagnostics.Debug.WriteLine(
        $"geometry: {geom_type}, empty: {is_empty}, sr_wkid {wkid} (shape)");
      return;
    default:
      //Blob? Others?
      var type_str = value.GetType().ToString();
      System.Diagnostics.Debug.WriteLine($"Primitive: {type_str}");
      return;
  }
}

// ...submit query or search
//using (var kg_rc = kg.SubmitQuery(kg_qf)) {
//using (var kg_rc = kg.SubmitSearch(kg_sf)) {
//  ...wait for rows ...
//  while (await kg_rc.WaitForRowsAsync()) {
//   ...rows have been retrieved
//   while (kg_rc.MoveNext()) {
//     ...get the current KnowledgeGraphRow
//     using (var graph_row = kg_rc.Current) {
//        var val_count = (int)graph_row.GetCount();
//        for (int i = 0; i<val_count; i++)
//           ProcessKnowledgeGraphRowValue(graph_row[i]);
Requirements

Target Platforms: Windows 11, Windows 10

ArcGIS Pro version: 3.2 or higher.
See Also