'______________________________________________________________
'                 G E T T I N G   T O   K N O W   L I N Q   Step 3

'                                     C# VERSION
'                                      Ron Kessler
'                                         2/5/09


'  _____________________________________________________________


' This time lets limit the number of records to the category they choose from the drop down.
' BE SURE TO SET THIS AS THE STARTUP PAGE IN THE SOLUTION EXPLORER
Option Explicit On


Imports System.Linq

Partial Class Step3
    Inherits System.Web.UI.Page

    Dim dc As New AdventureworksDataContext


    Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load



        If (Not Page.IsPostBack) Then

            '---create the LINQ SQL to fill the list box

            Dim categories = From cat In dc.ProductCategories _
                                     Select cat

            ddlCategory.DataSource = categories
            ddlCategory.DataValueField = "ProductCategoryID"    'data table column name
            ddlCategory.DataTextField = "Name"                        'data table column name


            '---now link up the grid to display our data


            ddlCategory.DataBind()      'make it so! 
        End If


    End Sub

    Protected Sub ddlCategory_SelectedIndexChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles ddlCategory.SelectedIndexChanged

        '---in the select statement where I want to format $, make sure to use
        '    an alias for the Grid column...I used "Price". You cannot use eachProduct.ListPrice
        '    or it will blow up!

        Dim products = From eachproduct In dc.Products _
                       Where (eachproduct.ProductCategoryID = Integer.Parse(ddlCategory.SelectedValue)) _
                       Order By eachproduct.Color _
                       Select eachproduct.ProductNumber, _
                                eachproduct.Name, eachproduct.Color, _
                                Price = String.Format("{0:n2}", eachproduct.ListPrice)



        GridView1.DataSource = products
        GridView1.DataBind()      'make it so!
    End Sub
End Class