OleDbEnumerator.GetRootEnumerator Method

Definition

Namespace:

System.Data.OleDb

Assembly:

System.Data.OleDb.dll

Package:

System.Data.OleDb v9.0.0-rc.2.24473.5

Source:

OleDbEnumerator.cs

Returns an OleDbDataReader that contains information about the currently installed OLE DB providers, without requiring an instance of the OleDbEnumerator class.

public:
 static System::Data::OleDb::OleDbDataReader ^ GetRootEnumerator();

public static System.Data.OleDb.OleDbDataReader GetRootEnumerator ();

static member GetRootEnumerator : unit -> System.Data.OleDb.OleDbDataReader

Public Shared Function GetRootEnumerator () As OleDbDataReader

Returns

OleDbDataReader

A OleDbDataReader that contains information about the visible OLE DB providers.

Exceptions

InvalidCastException

The provider does not support ISourcesRowset.

OleDbException

Exception has occurred in the underlying provider.

Examples

The following console application retrieves information about all the visible OLE DB providers and displays the information in the console window.

Imports System.Data  
Imports System.Data.OleDb  

Module Module1  

  Sub Main()  
    Dim enumerator As New OleDbEnumerator  
    Dim reader As OleDbDataReader = OleDbEnumerator.GetRootEnumerator()  

    DisplayData(reader)  

    Console.WriteLine("Press any key to continue.")  
    Console.ReadKey()  
  End Sub  

  Private Sub DisplayData(ByVal reader As OleDbDataReader)  
    While reader.Read()  
      For i As Integer = 0 To reader.FieldCount - 1  
        Console.WriteLine("{0} = {1}", _  
         reader.GetName(i), reader.GetValue(i))  
      Next  
      Console.WriteLine("==================================")  
    End While  

  End Sub  
End Module  

using System;  
using System.Data;  
using System.Data.OleDb;  

class Program  
{  
 static void Main()  
 {  
   OleDbDataReader reader = OleDbEnumerator.GetRootEnumerator();  

   DisplayData(reader);  

   Console.WriteLine("Press any key to continue.");  
   Console.ReadKey();  
 }  

 static void DisplayData(OleDbDataReader reader)  
 {  
   while (reader.Read())  
   {  
     for (int i = 0; i < reader.FieldCount; i++)  
     {  
       Console.WriteLine("{0} = {1}",  
        reader.GetName(i), reader.GetValue(i));  
     }  
     Console.WriteLine("==================================");  
   }  
 }  
}  

Remarks

The reader returned by this method contains the following columns, all of which contain strings:

Column Ordinal	Column	Description
0	SOURCES_NAME	The invariant name of the native OLEDB data source or enumerator.
1	SOURCES_PARSENAME	A human-readable name that can be converted to a moniker using the native COM interface IParseDisplayName. Corresponds to the SOURCES_PARSENAME column returned by the native OLE DB sources rowset.
2	SOURCES_DESCRIPTION	Description of the native OLE DB data source. Corresponds to the SOURCES_DESCRIPTION column returned by the native OLE DB sources rowset.
3	SOURCES_TYPE	One of the following enumeration members: Binder (0), DataSource_MDP (1), DataSource_TDP (2), Enumerator (3). These correspond to the values returned in the SOURCES_TYPE column of the native OLE DB sources rowset.
4	SOURCES_ISPARENT	Applicable to enumerators only. If true, indicates that the entry applies to the same enumerator on which GetSourcesRowset was called, implying that it is also included in the sub-enumeration. Corresponds to the SOURCES_ISPARENT column of the native OLE DB sources rowset
5	SOURCES_CLSID	A human-readable name, that can be converted to a moniker using the native COM interface IParseDisplayName. Corresponds to the SOURCES_CLSID column returned by the native OLE DB sources rowset.