SqlDataAdapter.SelectCommand Propriedade
Definição
Importante
Algumas informações dizem respeito a um produto pré-lançado que pode ser substancialmente modificado antes de ser lançado. A Microsoft não faz garantias, de forma expressa ou implícita, em relação à informação aqui apresentada.
Obtém ou define uma instrução Transact-SQL ou procedimento armazenado usado para selecionar registos na fonte de dados.
public:
property System::Data::SqlClient::SqlCommand ^ SelectCommand { System::Data::SqlClient::SqlCommand ^ get(); void set(System::Data::SqlClient::SqlCommand ^ value); };
[System.Data.DataSysDescription("DbDataAdapter_SelectCommand")]
public System.Data.SqlClient.SqlCommand SelectCommand { get; set; }
public System.Data.SqlClient.SqlCommand SelectCommand { get; set; }
[<System.Data.DataSysDescription("DbDataAdapter_SelectCommand")>]
member this.SelectCommand : System.Data.SqlClient.SqlCommand with get, set
member this.SelectCommand : System.Data.SqlClient.SqlCommand with get, set
Public Property SelectCommand As SqlCommand
Valor de Propriedade
A foi usado durante Fill(DataSet) para selecionar registos da base de dados para colocação SqlCommand no DataSet.
- Atributos
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
Quando SelectCommand é atribuído a um criado SqlCommandanteriormente , o SqlCommand não é clonado. O SelectCommand mantém uma referência ao objeto previamente criado SqlCommand .
Se o SelectCommand não devolver quaisquer linhas, não são adicionadas tabelas ao DataSet, e nenhuma exceção é levantada.