Enumerating Installed Data Providers
Each installed data provider that supports a factory-based class registers configuration information in the machine.config file on the local computer in the DbProviderFactories section. The following configuration file fragment shows the syntax and format for System.Data.SqlClient.
<system.data>
<DbProviderFactories>
<add name="SqlClient Data Provider"
invariant="System.Data.SqlClient"
description=".Net Framework Data Provider for SqlServer"
type="System.Data.SqlClient.SqlClientFactory, System.Data,
Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089"
/>
</DbProviderFactories>
</system.data>
Retrieving Provider Information
You can retrieve information about all of the data providers installed on the local computer by using the GetFactoryClasses method. It returns a DataTable named DbProviderFactories that contains the columns described in the following table.
| Column ordinal | Column name | Example output | Description |
|---|---|---|---|
| 0 | Name | SqlClient Data Provider | Readable name for the data provider |
| 1 | Description | .Net Framework Data Provider for SqlServer | Readable description of the data provider |
| 2 | InvariantName | System.Data.SqlClient | Name that can be used programmatically to refer to the data provider |
| 3 | AssemblyQualifiedName | System.Data.SqlClient.SqlClientFactory, System.Data, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089 | Fully qualified name of the factory class, which contains enough information to instantiate the object |
This DataTable can be used to enable a user to select a DataRow at run time. The selected DataRow can then be passed to the GetFactory method to create a strongly typed DbProviderFactory. For more information on creating factories, see Working with Factories.
GetFactoryClasses Example
This example demonstrates how to use the GetFactoryClasses method to return a DataTable containing information about the installed providers. The code iterates through each row in the DataTable, displaying information for each installed provider in the console window.
// This example assumes a reference to System.Data.Common. static DataTable GetProviderFactoryClasses() { // Retrieve the installed providers and factories. DataTable table = DbProviderFactories.GetFactoryClasses(); // Display each row and column value. foreach (DataRow row in table.Rows) { foreach (DataColumn column in table.Columns) { Console.WriteLine(row[column]); } } return table; }
