SqlDataAdapter.SelectCommand Свойство

Определение

Пространство имен:
System.Data.SqlClient
Сборка:
System.Data.SqlClient.dll
Сборка:
System.Data.dll

Возвращает или задает инструкцию Transact-SQL или хранимую процедуру, используемую для выбора записей из источника данных.Gets or sets a Transact-SQL statement or stored procedure used to select records in the data source.

public:
 property System::Data::SqlClient::SqlCommand ^ SelectCommand { System::Data::SqlClient::SqlCommand ^ get(); void set(System::Data::SqlClient::SqlCommand ^ value); };
public System.Data.SqlClient.SqlCommand SelectCommand { get; set; }
[System.Data.DataSysDescription("DbDataAdapter_SelectCommand")]
public System.Data.SqlClient.SqlCommand SelectCommand { get; set; }
member this.SelectCommand : System.Data.SqlClient.SqlCommand with get, set
[<System.Data.DataSysDescription("DbDataAdapter_SelectCommand")>]
member this.SelectCommand : System.Data.SqlClient.SqlCommand with get, set
Public Property SelectCommand As SqlCommand

Значение свойства

SqlCommand

SqlCommand, используемый во время выполнения Fill(DataSet) для выбора записей из базы данных для помещения в DataSet.A SqlCommand used during Fill(DataSet) to select records from the database for placement in the DataSet.

Атрибуты
DataSysDescriptionAttribute

Примеры

В следующем примере создается SqlDataAdapter и задаются SelectCommand InsertCommand свойства,, UpdateCommand и DeleteCommand .The following example creates a SqlDataAdapter and sets the SelectCommand, InsertCommand, UpdateCommand, and DeleteCommand properties. Предполагается, что объект уже создан SqlConnection .It assumes you have already created a SqlConnection object.

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

Комментарии

Когда SelectCommand назначается ранее созданному SqlCommand , объект SqlCommand не клонируется.When SelectCommand is assigned to a previously created SqlCommand, the SqlCommand is not cloned. Объект SelectCommand поддерживает ссылку на ранее созданный SqlCommand объект.The SelectCommand maintains a reference to the previously created SqlCommand object.

Если не SelectCommand возвращает ни одной строки, ни одна из таблиц не добавляется в DataSet , а исключение не возникает.If the SelectCommand does not return any rows, no tables are added to the DataSet, and no exception is raised.

Применяется к

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