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DbSeekOptions Enumeration

Options that specify how the Seek method will seek on an index.

This enumeration has a FlagsAttribute attribute that allows a bitwise combination of its member values.

Namespace:  System.Data.SqlServerCe
Assembly:  System.Data.SqlServerCe (in System.Data.SqlServerCe.dll)

'Declaration
<FlagsAttribute> _
Public Enumeration DbSeekOptions
'Usage
Dim instance As DbSeekOptions

Member nameDescription
FirstEqualAdvances to the first matching row (in index order) on the index.
LastEqualAdvances to the last matching row (in index order) on the index.
AfterEqualAdvances to the last matching row on the index. If there are no matching rows, advances to the first row with values after the seek value, in index order.
AfterAdvances to the first row with values (in index order) after the seek value.
BeforeEqualAdvances to the first matching row on the index. If there are no matching rows, advances to the last row with values before the seek value, in index order.
BeforeAdvances to the last row with values (in index order) before the seek value.

In this example, the FirstEqual option is specified for the Seek operation on the index.

        Try
            Dim conn As New SqlCeConnection("Data Source = MyDatabase.sdf")
            conn.Open()

            Dim cmd As SqlCeCommand = conn.CreateCommand()
            cmd.CommandType = CommandType.TableDirect
            cmd.IndexName = "Orders_PK"
            cmd.CommandText = "Orders"

            ' We are interested in orders that match Order ID = 10020
            '
            cmd.SetRange(DbRangeOptions.Match, New Object() {10020}, Nothing)

            Dim reader As SqlCeDataReader = cmd.ExecuteReader(CommandBehavior.Default)

            While reader.Read()
                MessageBox.Show(String.Format("{0} ; {1}", reader("Order ID"), reader("Order Date")))
            End While

            ' Now we are interested in orders with Order ID between (10020, 10050)
            '
            cmd.SetRange(DbRangeOptions.InclusiveStart Or DbRangeOptions.InclusiveEnd, New Object() {10020}, New Object() {10050})

            reader = cmd.ExecuteReader(CommandBehavior.Default)

            ' Now seek to Order ID = 10045
            '
			Dim onRow As Boolean =  reader.Seek(DbSeekOptions.FirstEqual, New Object() {10045})

            ' Now ,the reader will return rows with Order ID >= 10045 <= 10050
            ' because the range was set to (10020, 10050)
            '
            If onRow Then
				While reader.Read()
					MessageBox.Show(String.Format("{0} ; {1}", reader("Order ID"), reader("Order Date")))
				End While
            End If
        Catch e As Exception
            MessageBox.Show(e.Message)
        End Try


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