ArcGIS Explorer Component Help |
Index Constructor (String) |
Index Class Example See Also |
Initializes a new instance of the Index class which can be used to create a new, single-column index on disk
when it is added to the IndexCollection. This constructor applies to file geodatabase tables/feature classes or shapefiles,
but is particularly useful for shapefiles which do not support user-named indexes.
Namespace:
ESRI.ArcGISExplorer.DataAssembly: ESRI.ArcGISExplorer (in ESRI.ArcGISExplorer.dll) Version: 2.0.0.1500 (2.0.0.1500)
Syntax
C# |
---|
public Index( string columnName ) |
Visual Basic (Declaration) |
---|
Public Sub New ( _ columnName As String _ ) |
Parameters
- columnName
- Type: System..::.String
The name of the Column to Index.
Remarks
The following properties use their default values:
- Name property is set to the name of the Column.
- IsUnique property is set to falseFalsefalsefalse (False in Visual Basic).
- IsAscending property is set to trueTruetruetrue (True in Visual Basic).
Examples
The code below demonstrates how to create a new index on a single column in a shapefile. A new Index object is
created with the name of the column to index being specified in the class constructor. The Index object is
then added to the IndexCollection to create the index on disk. The properties of the Index object are printed out.
CopyC#
{ //Open the cities shapefile Table citiesTable = Table.OpenShapefile(@"C:\Data\World\Cities.shp"); //Get the IndexCollection IndexCollection indexes = citiesTable.Indexes; //Create a new Index object for the Name Column Index nameIndex = new Index("Name"); try { //Add the Index to the IndexCollection thereby creating it on disk. //A file called cities.NAME.atx will be created in the C:\Data\World\ directory. indexes.Add(nameIndex); //Print out the index properties System.Diagnostics.Debug.Print(nameIndex.Name); //Prints "Name" System.Diagnostics.Debug.Print(nameIndex.IsAscending.ToString()); //Prints "True" System.Diagnostics.Debug.Print(nameIndex.IsUnique.ToString()); //Prints "False" } catch (Exception ex) { System.Diagnostics.Debug.Print(ex.Message); } }
CopyVB.NET
'Open the cities shapefile Dim citiesTable As Table = Table.OpenShapefile("C:\Data\World\Cities.shp") 'Get the IndexCollection Dim indexes As IndexCollection = citiesTable.Indexes 'Create a new Index object for the Name Column Dim nameIndex As Index = New Index("Name") Try 'Add the Index to the IndexCollection thereby creating it on disk. 'A file called cities.NAME.atx will be created in the C:\Data\World\ directory. indexes.Add(nameIndex) 'Print out the index properties System.Diagnostics.Debug.Print(nameIndex.Name) 'Prints "Name" System.Diagnostics.Debug.Print(nameIndex.IsAscending.ToString()) 'Prints "True" System.Diagnostics.Debug.Print(nameIndex.IsUnique.ToString()) 'Prints "False" Catch ex As Exception System.Diagnostics.Debug.Print(ex.Message) End Try