SqlClientFactory.CanCreateDataSourceEnumerator Properti

Definisi

Ruang nama:

System.Data.SqlClient

Rakitan:

System.Data.dll

Mendapatkan nilai yang menunjukkan apakah SqlDataSourceEnumerator dapat dibuat.

public:
 virtual property bool CanCreateDataSourceEnumerator { bool get(); };

public override bool CanCreateDataSourceEnumerator { get; }

member this.CanCreateDataSourceEnumerator : bool

Public Overrides ReadOnly Property CanCreateDataSourceEnumerator As Boolean

Nilai Properti

Boolean

trueSqlDataSourceEnumerator jika dapat dibuat; jika tidak, false.

Contoh

Contoh berikut menampilkan daftar semua sumber data SQL Server yang tersedia, menggunakan kode yang dapat menghitung sumber data untuk penyedia mana pun.

using System;
using System.Data;
using System.Data.Common;
using System.Data.SqlClient;

class Program
{
    static void Main()
    {
        // List all SQL Server instances:
        ListServers(SqlClientFactory.Instance);

        Console.WriteLine();
        Console.WriteLine("Press any key to continue...");
        Console.ReadKey();
    }
    private static void ListServers(DbProviderFactory factory)
    {
        // This procedure is provider-agnostic, and can list
        // instances of any provider's servers. Of course,
        // not all providers can create a data source enumerator,
        // so it's best to check the CanCreateDataSourceEnumerator
        // property before attempting to list the data sources.
        if (factory.CanCreateDataSourceEnumerator)
        {
            DbDataSourceEnumerator instance =
                factory.CreateDataSourceEnumerator();
            DataTable table = instance.GetDataSources();

            foreach (DataRow row in table.Rows)
            {
                Console.WriteLine("{0}\\{1}",
                    row["ServerName"], row["InstanceName"]);
            }
        }
    }
}

Imports System.Data
Imports System.Data.Common
Imports System.Data.SqlClient

Module Module1
    Sub Main()
        ' List all SQL Server instances:
        ListServers(SqlClientFactory.Instance)

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

    Private Sub ListServers(ByVal factory As DbProviderFactory)
        ' This procedure is provider-agnostic, and can list
        ' instances of any provider's servers. Of course, 
        ' not all providers can create a data source enumerator,
        ' so it's best to check the CanCreateDataSourceEnumerator property
        ' before attempting to list the data sources.
        If factory.CanCreateDataSourceEnumerator Then
            Dim instance As DbDataSourceEnumerator = _
             factory.CreateDataSourceEnumerator
            Dim table As System.Data.DataTable = instance.GetDataSources()

            Dim row As DataRow
            For Each row In table.Rows
                Console.WriteLine("{0}\{1}", _
                 row("ServerName"), row("InstanceName"))
            Next
        End If
    End Sub
End Module

Keterangan

Kelas DbProviderFactory menyediakan CanCreateDataSourceEnumerator properti sehingga pewaris dapat menunjukkan apakah mereka dapat menyediakan enumerator sumber data. menampilkan SqlClientFactory properti ini, tetapi nilainya selalu true.

Lihat juga

• Ringkasan ADO.NET