this post is a cut and paste from the vb.net forums that i posted a few days ago - i'm trying to figure out how to display as an integer the count of records returned from a query to a domain service - cut and paste is below:
This post is somewhat of a hybrid as it involves vbcode directly but is being called from silverlight, so i thought i'd mention it here first.
i'm trying to get an integer number from a query that reflects the count of rows returned.
i have a domainservice called loginservice.vb containing the following:
and i have a mainpage.xaml.vb with a button on it that queries a database to see if there is a matching username and password - if the count is 0 i'd like to prompt the user that their credentials are no good, if the count is 1 (ie it found the user and password) then they can come in......
Public Function GetLoginsByName(ByVal username As String, ByVal password As String) As IQueryable(Of login)
Return Me.ObjectContext.logins.Where(Function(t) t.username = username AndAlso t.password = password)
here's the buttonclick code:
the datagrid is only there so that i could see the data was already being returned correctly....and it is - i just want to see if the query returns a result or if it does not.....
Private Sub btnLogin_Click(ByVal sender As System.Object, ByVal e As System.Windows.RoutedEventArgs) Handles btnLogin.Click
Dim username As String = tbUserName.Text
Dim password As String = pbPassword.Password
Dim context = New LoginContext()
context.GetLoginsByNameQuery(username, password).IncludeTotalCount = True
DataGrid1.ItemsSource = context.logins
Label3.Content = context.logins.EntityContainer.EntitySets.ElementAt(0).Count
i've looked at the includetotalcount items but no such luck.....any help would be appreciated.
oh and label 3 is only for debugging so i can see if it will return 0 or 1....and in this case, always returns a 0 even if it finds a match in the table, so clearly i'm trying to get the count the wrong way, i'm just not sure what the syntax is for the right way.