SqlCeCommand.ExecuteReader Method (CommandBehavior)

Article
10/22/2009

Sends the CommandText to the Connection and builds a SqlCeDataReader by using one of the CommandBehavior values.

Namespace: System.Data.SqlServerCe
Assembly: System.Data.SqlServerCe (in system.data.sqlserverce.dll)

Syntax

'Declaration
Public Function ExecuteReader ( _
    behavior As CommandBehavior _
) As SqlCeDataReader

public SqlCeDataReader ExecuteReader (
    CommandBehavior behavior
)

public:
SqlCeDataReader^ ExecuteReader (
    CommandBehavior behavior
)

public SqlCeDataReader ExecuteReader (
    CommandBehavior behavior
)

public function ExecuteReader (
    behavior : CommandBehavior
) : SqlCeDataReader

Parameters

behavior
One of the CommandBehavior values.

Return Value

A SqlCeDataReader object.

Exceptions

Exception type	Condition
InvalidOperationException	Cannot execute a command within a transaction context that differs from the context in which the connection was originally enlisted.

Remarks

The SqlCeDataReader supports a special mode that enables large binary values to be read efficiently. For more information, see the SequentialAccess setting for CommandBehavior.

While the SqlCeDataReader is in use, the associated SqlCeConnection is busy serving the SqlCeDataReader. In this state, until you call the Close method of the SqlCeDataReader, you can perform only the Close operation on the SqlCeConnection.

Example

The following example creates a SqlCeCommand, and then executes it by passing an SQL SELECT statement and a SqlCeConnection object. CommandBehavior is set to CloseConnection.

Dim conn As New SqlCeConnection(connString)
Dim cmd As New SqlCeCommand("SELECT * FROM myTable", conn)

cmd.Connection.Open()
Dim rdr As SqlCeDataReader = Nothing

Try
    ' Execute the reader; make sure you alway close the 
    ' reader after you're done using it (ideally in the finally block)
    '
    rdr = cmd.ExecuteReader(CommandBehavior.CloseConnection)

    While rdr.Read()
        Console.WriteLine(rdr.GetString(0))
    End While
Finally
    ' Closing the reader will also close the associated connection
    '
    rdr.Close()
End Try

SqlCeConnection conn = new SqlCeConnection(connString);
SqlCeCommand cmd = new SqlCeCommand("SELECT * FROM myTable", conn);

cmd.Connection.Open();
SqlCeDataReader rdr = null;

try
{
    // Execute the reader; make sure you alway close the 
    // reader after you're done using it (ideally in the finally block)
    //
    rdr = cmd.ExecuteReader(CommandBehavior.CloseConnection);

    while (rdr.Read())
    {
        Console.WriteLine(rdr.GetString(0));
    }
}
finally
{
    // Closing the reader will also close the associated connection
    //
    rdr.Close();
}

Thread Safety

Any public static (Shared in Microsoft Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

Platforms

Development Platforms

Windows Vista, Windows Mobile 5.0, Windows XP Professional with Service Pack 2 (SP2), Windows Server 2003, Windows Mobile 2003 for Pocket PC, Windows CE 5.0
Version Information
.NET Framework and NET Compact Framework
Supported in 3.5
.NET Framework
Supported in 3.0
.NET Compact Framework and .Net Framework
Supported in 2.0