OdbcDataAdapter.DeleteCommand Properti

Definisi

Ruang nama:

System.Data.Odbc

Rakitan:

System.Data.Odbc.dll

Paket:

System.Data.Odbc v9.0.0-preview.5.24306.7

Sumber:

OdbcDataAdapter.cs

Mendapatkan atau mengatur pernyataan SQL atau prosedur tersimpan yang digunakan untuk menghapus rekaman di sumber data.

public:
 property System::Data::Odbc::OdbcCommand ^ DeleteCommand { System::Data::Odbc::OdbcCommand ^ get(); void set(System::Data::Odbc::OdbcCommand ^ value); };

public System.Data.Odbc.OdbcCommand? DeleteCommand { get; set; }

member this.DeleteCommand : System.Data.Odbc.OdbcCommand with get, set

Public Property DeleteCommand As OdbcCommand

Nilai Properti

OdbcCommand

Yang OdbcCommand digunakan selama operasi pembaruan untuk menghapus rekaman di sumber data yang sesuai dengan baris yang dihapus di DataSet.

Contoh

Contoh berikut membuat OdbcDataAdapter dan mengatur SelectCommand properti dan DeleteCommand . Ini mengasumsikan bahwa Anda telah membuat OdbcConnection objek.

public static OdbcDataAdapter CreateDataAdapter(
    OdbcConnection connection)
{
    string selectCommand =
        "SELECT CustomerID, CompanyName FROM Customers";

    OdbcDataAdapter adapter = new OdbcDataAdapter(
        selectCommand, connection);
    adapter.MissingSchemaAction = MissingSchemaAction.AddWithKey;

    // Create the Insert, Update and Delete commands.
    adapter.InsertCommand = new OdbcCommand(
        "INSERT INTO Customers (CustomerID, CompanyName) " +
        "VALUES (?, ?)");

    adapter.UpdateCommand = new OdbcCommand(
        "UPDATE Customers SET CustomerID = ?, CompanyName = ? " +
        "WHERE CustomerID = ?");

    adapter.DeleteCommand = new OdbcCommand(
        "DELETE FROM Customers WHERE CustomerID = ?");

    // Create the parameters.
    adapter.InsertCommand.Parameters.Add("@CustomerID",
        OdbcType.Char, 5, "CustomerID");
    adapter.InsertCommand.Parameters.Add("@CompanyName",
        OdbcType.VarChar, 40, "CompanyName");

    adapter.UpdateCommand.Parameters.Add("@CustomerID",
        OdbcType.Char, 5, "CustomerID");
    adapter.UpdateCommand.Parameters.Add("@CompanyName",
        OdbcType.VarChar, 40, "CompanyName");
    adapter.UpdateCommand.Parameters.Add("@oldCustomerID",
        OdbcType.Char, 5, "CustomerID").SourceVersion =
        DataRowVersion.Original;

    adapter.DeleteCommand.Parameters.Add("@CustomerID",
        OdbcType.Char, 5, "CustomerID").SourceVersion =
        DataRowVersion.Original;

    return adapter;
}

Public Function CreateDataAdapter( _
    ByVal connection As OdbcConnection) As OdbcDataAdapter

    Dim selectCommand As String = _
        "SELECT CustomerID, CompanyName FROM Customers"
    Dim adapter As OdbcDataAdapter = _
        New OdbcDataAdapter(selectCommand, connection)

    adapter.MissingSchemaAction = MissingSchemaAction.AddWithKey

    ' Create the Insert, Update and Delete commands.
    adapter.InsertCommand = New OdbcCommand( _
        "INSERT INTO Customers (CustomerID, CompanyName) " & _
         "VALUES (?, ?)")

    adapter.UpdateCommand = New OdbcCommand( _
        "UPDATE Customers SET CustomerID = ?, CompanyName = ? " & _
        "WHERE CustomerID = ?")

    adapter.DeleteCommand = New OdbcCommand( _
        "DELETE FROM Customers WHERE CustomerID = ?")

    ' Create the parameters.
    adapter.InsertCommand.Parameters.Add( _
        "@CustomerID", OdbcType.Char, 5, "CustomerID")
    adapter.InsertCommand.Parameters.Add( _
        "@CompanyName", OdbcType.VarChar, 40, "CompanyName")

    adapter.UpdateCommand.Parameters.Add( _
        "@CustomerID", OdbcType.Char, 5, "CustomerID")
    adapter.UpdateCommand.Parameters.Add( _
        "@CompanyName", OdbcType.VarChar, 40, "CompanyName")
    adapter.UpdateCommand.Parameters.Add( _
        "@oldCustomerID", OdbcType.Char, 5, "CustomerID").SourceVersion = _
        DataRowVersion.Original

    adapter.DeleteCommand.Parameters.Add( _
        "@CustomerID", OdbcType.Char, 5, "CustomerID").SourceVersion = _
        DataRowVersion.Original

    Return adapter
End Function

Keterangan

DeleteCommand Ketika properti ditetapkan ke yang dibuat OdbcCommandsebelumnya, OdbcCommand properti tidak dikloning. Sebaliknya, DeleteCommand mempertahankan referensi ke yang dibuat OdbcCommandsebelumnya.

Selama operasi pembaruan, jika DeleteCommand tidak diatur dan informasi kunci utama ada di DataSet, Anda dapat menggunakan OdbcCommandBuilder kelas untuk secara otomatis menghasilkan DeleteCommand, dan perintah tambahan yang diperlukan untuk merekonsiliasi DataSet ke sumber data. Untuk melakukan ini, atur SelectCommand properti dari OdbcDataAdapter. Logika pembuatan juga memerlukan informasi kolom kunci untuk hadir di DataSet. Untuk mendapatkan informasi selengkapnya, lihat Menghasilkan Perintah dengan CommandBuilders.

Lihat juga

• DataAdapters dan DataReaders