VB.NET DataServiceContext.LoadProperty方法代码示例

' Create the DataServiceContext using the service URI.
Dim context = New NorthwindEntities(svcUri)

Try
    ' Enumerate over the top 10 orders obtained from the context.
    For Each order As Order In context.Orders.Take(10)
        ' Explicitly load the customer for each order.
        context.LoadProperty(order, "Customer")

        ' Write out customer and order information.
        Console.WriteLine("Customer: {0} - Order ID: {1}", _
                order.Customer.CompanyName, order.OrderID)
    Next
Catch ex As DataServiceQueryException
    Throw New ApplicationException( _
            "An error occurred during query execution.", ex)
End Try

' Create the DataServiceContext using the service URI.
Dim context = New NorthwindEntities(svcUri)
Dim nextLink As DataServiceQueryContinuation(Of Customer) = Nothing
Dim pageCount = 0
Dim innerPageCount = 0

Try
    ' Execute the query for all customers and related orders,
    ' and get the response object.
    Dim response = _
    CType(context.Customers.AddQueryOption("$expand", "Orders") _
            .Execute(), QueryOperationResponse(Of Customer))

    ' With a paged response from the service, use a do...while loop 
    ' to enumerate the results before getting the next link.
    Do
        ' Write the page number.
        Console.WriteLine("Customers Page {0}:", ++pageCount)

        ' If nextLink is not null, then there is a new page to load.
        If nextLink IsNot Nothing Then
            ' Load the new page from the next link URI.
            response = CType(context.Execute(Of Customer)(nextLink),  _
                    QueryOperationResponse(Of Customer))
        End If

        ' Enumerate the customers in the response.
        For Each c As Customer In response
            Console.WriteLine(vbTab & "Customer Name: {0}", c.CompanyName)
            Console.WriteLine(vbTab & "Orders Page {0}:", innerPageCount + 1)

            ' Get the next link for the collection of related Orders.
            Dim nextOrdersLink As DataServiceQueryContinuation(Of Order) = _
            response.GetContinuation(c.Orders)

            While nextOrdersLink IsNot Nothing
                For Each o As Order In c.Orders
                    ' Print out the orders.
                    Console.WriteLine(vbTab & vbTab & "OrderID: {0} - Freight: ${1}", _
                            o.OrderID, o.Freight)
                Next
                ' Load the next page of Orders.
                Dim ordersResponse = _
                context.LoadProperty(c, "Orders", nextOrdersLink)
                nextOrdersLink = ordersResponse.GetContinuation()
            End While
        Next
        ' Get the next link, and continue while there is a next link.
        nextLink = response.GetContinuation()
    Loop While nextLink IsNot Nothing
Catch ex As DataServiceQueryException
    Throw New ApplicationException( _
            "An error occurred during query execution.", ex)
End Try