Adds a new Index to the IndexCollection and creates a new physical index on disk.
Namespace:
ESRI.ArcGISExplorer.DataAssembly: ESRI.ArcGISExplorer (in ESRI.ArcGISExplorer.dll) Version: 2.0.0.1500 (2.0.0.1500)
Syntax
Parameters
- index
- Type: ESRI.ArcGISExplorer.Data..::.Index
An Index object which represents a internally-managed table allowing any Row in a Table to be retrieved quickly.
Remarks
Indexes can not be added for data stored in an ArcSDE geodatabase.
The two most common reasons for the Add method to fail are:
- A schema lock cannot be acquired on the Table, for example the feature class is currently being edited in ArcGIS Desktop.
- A shapefile is contained in directory with read-only permissions.
For spatially enabled tables, it is possible to create a new spatial index against the Column storing the geometries (usually the Shape column) but the ArcGIS Explorer API does not provide any mechanism to specify the grid sizes for this index.
Examples
The code below, which would be suitable for a dockable window add-in, presents a scenario where the user can
build an index against any column in the selected feature layer. The Add method is used to add the
Index to the IndexCollection, thereby creating it on disk.
CopyC#
//Get first selected map item MapItem firstSelectedMapItem = ESRI.ArcGISExplorer.Application.Application.SelectedItems[0]; //Exit if either no selection or if selection is not a FeatureLayer if ((firstSelectedMapItem == null) || !(firstSelectedMapItem is FeatureLayer)) return; //Get selected feature layer FeatureLayer someFeatureLayer = firstSelectedMapItem as FeatureLayer; //Get the Table Table someTable = someFeatureLayer.Table; //Indexes cannot be created for ArcSDE data so check for this. object dataContainer = someTable.RootDataContainer; if (dataContainer is Geodatabase) { Geodatabase gdb = dataContainer as Geodatabase; if (gdb.Type == GeodatabaseType.ArcSDE) return; } //Get the IndexCollection for the Table IndexCollection indexes = someTable.Indexes; //Simulated code to represent a user selecting an item from a list of column names System.Windows.Forms.ListBox columnsListBox = new System.Windows.Forms.ListBox(); string columnName = columnsListBox.SelectedItem.ToString(); //Check whether the column already participates in any indexes if (indexes.FindIndexesByColumnName(columnName).Count == 0) { try { //Create the new index string indexName = string.Format("idx_ {0}",columnName); Index newIndex = new Index(indexName, columnName); //if shapefile the index name parameter will be ignored //Add it to the IndexCollection indexes.Add(newIndex); } catch (Exception ex) { System.Windows.Forms.MessageBox.Show(string.Format("It was not possible to build an index for the {0} column: {1}",columnName, ex.Message)); } }
CopyVB.NET
'Get first selected map item Dim firstSelectedMapItem As MapItem = ESRI.ArcGISExplorer.Application.Application.SelectedItems.Item(0) 'Exit if either no selection or if selection is not a FeatureLayer If firstSelectedMapItem Is Nothing Or Not TypeOf firstSelectedMapItem Is FeatureLayer Then Return End If 'Get selected feature layer Dim someFeatureLayer As FeatureLayer = DirectCast(firstSelectedMapItem, FeatureLayer) 'Get the Table Dim someTable As Table = someFeatureLayer.Table 'Indexes cannot be created for ArcSDE data so check for this. Dim dataContainer As Object = someTable.RootDataContainer If TypeOf dataContainer Is Geodatabase Then Dim gdb As Geodatabase = DirectCast(dataContainer, Geodatabase) If gdb.Type = GeodatabaseType.ArcSDE Then Return End If End If 'Get the IndexCollection for the Table Dim indexes As IndexCollection = someTable.Indexes 'Simulated code to represent a user selecting an item from a list of column names Dim columnsListBox As System.Windows.Forms.ListBox = New System.Windows.Forms.ListBox() Dim columnName As String = columnsListBox.SelectedItem.ToString() 'Check whether the column already participates in any indexes If indexes.FindIndexesByColumnName(columnName).Count = 0 Then Try 'Create the new index Dim indexName As String = String.Format("idx_ 0", columnName) Dim newIndex As Index = New Index(indexName, columnName) 'if shapefile the index name parameter will be ignored 'Add it to the IndexCollection indexes.Add(newIndex) Catch ex As Exception System.Windows.Forms.MessageBox.Show(String.Format("It was not possible to build an index for the 0 column: 1", columnName, ex.Message)) End Try End If