SqlDataAdapter.DeleteCommand Propriedade

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

[System.Data.DataSysDescription("DbDataAdapter_DeleteCommand")]
public System.Data.SqlClient.SqlCommand DeleteCommand { get; set; }

public System.Data.SqlClient.SqlCommand DeleteCommand { get; set; }

[<System.Data.DataSysDescription("DbDataAdapter_DeleteCommand")>]
member this.DeleteCommand : System.Data.SqlClient.SqlCommand with get, set

member this.DeleteCommand : System.Data.SqlClient.SqlCommand with get, set

Public Property DeleteCommand As SqlCommand

Valor de Propriedade

A SqlCommand foi usado durante Update(DataSet) para eliminar registos na base de dados que correspondem a linhas eliminadas no DataSetarquivo .

Atributos

DataSysDescriptionAttribute

Exemplos

O exemplo seguinte cria um SqlDataAdapter e define as SelectCommandpropriedades , InsertCommand, UpdateCommand, e DeleteCommand . Assume que já criaste um SqlConnection objeto.

public static SqlDataAdapter CreateCustomerAdapter(
    SqlConnection connection)
{
    SqlDataAdapter adapter = new SqlDataAdapter();

    // Create the SelectCommand.
    SqlCommand command = new SqlCommand("SELECT * FROM Customers " +
        "WHERE Country = @Country AND City = @City", connection);

    // Add the parameters for the SelectCommand.
    command.Parameters.Add("@Country", SqlDbType.NVarChar, 15);
    command.Parameters.Add("@City", SqlDbType.NVarChar, 15);

    adapter.SelectCommand = command;

    // Create the InsertCommand.
    command = new SqlCommand(
        "INSERT INTO Customers (CustomerID, CompanyName) " +
        "VALUES (@CustomerID, @CompanyName)", connection);

    // Add the parameters for the InsertCommand.
    command.Parameters.Add("@CustomerID", SqlDbType.NChar, 5, "CustomerID");
    command.Parameters.Add("@CompanyName", SqlDbType.NVarChar, 40, "CompanyName");

    adapter.InsertCommand = command;

    // Create the UpdateCommand.
    command = new SqlCommand(
        "UPDATE Customers SET CustomerID = @CustomerID, CompanyName = @CompanyName " +
        "WHERE CustomerID = @oldCustomerID", connection);

    // Add the parameters for the UpdateCommand.
    command.Parameters.Add("@CustomerID", SqlDbType.NChar, 5, "CustomerID");
    command.Parameters.Add("@CompanyName", SqlDbType.NVarChar, 40, "CompanyName");
    SqlParameter parameter = command.Parameters.Add(
        "@oldCustomerID", SqlDbType.NChar, 5, "CustomerID");
    parameter.SourceVersion = DataRowVersion.Original;

    adapter.UpdateCommand = command;

    // Create the DeleteCommand.
    command = new SqlCommand(
        "DELETE FROM Customers WHERE CustomerID = @CustomerID", connection);

    // Add the parameters for the DeleteCommand.
    parameter = command.Parameters.Add(
        "@CustomerID", SqlDbType.NChar, 5, "CustomerID");
    parameter.SourceVersion = DataRowVersion.Original;

    adapter.DeleteCommand = command;

    return adapter;
}

Public Function CreateCustomerAdapter( _
  ByVal connection As SqlConnection) As SqlDataAdapter

    Dim adapter As SqlDataAdapter = New SqlDataAdapter()

    ' Create the SelectCommand.
    Dim command As SqlCommand = New SqlCommand( _
        "SELECT * FROM Customers " & _
        "WHERE Country = @Country AND City = @City", connection)

    ' Add the parameters for the SelectCommand.
    command.Parameters.Add("@Country", SqlDbType.NVarChar, 15)
    command.Parameters.Add("@City", SqlDbType.NVarChar, 15)

    adapter.SelectCommand = command

    ' Create the InsertCommand.
    command = New SqlCommand( _
        "INSERT INTO Customers (CustomerID, CompanyName) " & _
        "VALUES (@CustomerID, @CompanyName)", connection)

    ' Add the parameters for the InsertCommand.
    command.Parameters.Add("@CustomerID", SqlDbType.NChar, 5, "CustomerID")
    command.Parameters.Add("@CompanyName", SqlDbType.NVarChar, 40, "CompanyName")

    adapter.InsertCommand = command

    ' Create the UpdateCommand.
    command = New SqlCommand( _
        "UPDATE Customers SET CustomerID = @CustomerID, CompanyName = @CompanyName " & _
        "WHERE CustomerID = @oldCustomerID", connection)

    ' Add the parameters for the UpdateCommand.
    command.Parameters.Add("@CustomerID", SqlDbType.NChar, 5, "CustomerID")
    command.Parameters.Add("@CompanyName", SqlDbType.NVarChar, 40, "CompanyName")
    Dim parameter As SqlParameter = command.Parameters.Add( _
        "@oldCustomerID", SqlDbType.NChar, 5, "CustomerID")
    parameter.SourceVersion = DataRowVersion.Original

    adapter.UpdateCommand = command

    ' Create the DeleteCommand.
    command = New SqlCommand( _
        "DELETE FROM Customers WHERE CustomerID = @CustomerID", connection)

    ' Add the parameters for the DeleteCommand.
    command.Parameters.Add( _
        "@CustomerID", SqlDbType.NChar, 5, "CustomerID")
    parameter.SourceVersion = DataRowVersion.Original

    adapter.DeleteCommand = command

    Return adapter
End Function

Observações

Durante Update, se esta propriedade não estiver definida e a informação da chave primária estiver presente no DataSet, pode DeleteCommand ser gerado automaticamente se definir a SelectCommand propriedade e usar o SqlCommandBuilder. Depois, quaisquer comandos adicionais que não definires são gerados pelo SqlCommandBuilder. Esta lógica de geração exige que a informação da coluna chave esteja presente no DataSet. Para obter mais informações, consulte Gerando comandos com CommandBuilders.

Quando DeleteCommand é atribuído a um criado SqlCommandanteriormente , o SqlCommand não é clonado. O DeleteCommand mantém uma referência ao objeto previamente criado SqlCommand .

Para cada coluna que propaga para a fonte de dados em Update, um parâmetro deve ser adicionado ao InsertCommand, UpdateCommand, ou DeleteCommand. A SourceColumn propriedade do parâmetro deve ser definida para o nome da coluna. Isto indica que o valor do parâmetro não é definido manualmente, mas é retirado da coluna específica na linha atualmente processada.

Ver também

• Manipulação de Dados (ADO.NET)
• Usando o Data Provider do .NET Framework para SQL Server
• Visão geral ADO.NET