How do I use Linq-to-sql to iterate db records?
I asked on SO a few days ago what was the simplest quickest way to build a wrapper around a recently completed database. I took the advice and used sqlmetal to build linq classes around my database design.
Now I am having two problems. One, I don't know LINQ. And, two, I have been shocked to realize how hard it is to learn. I have a book on LINQ (Linq In Action by Manning) and it has helped some but at the end of the day it is going to take me a couple of weeks to get traction and I need to make some progress on my project today.
So, I am looking for some help getting started.
Click HERE To see my simple database schema.
Click HERE to see the vb class that was generated for the schema.My needs are simple. I have a console app. The main table is the SupplyModel table. Most of the other tables are child tables of the SupplyModel table.
I want to iterate through each of Supply Model records. I want to grab the data for a supply model and then DoStuff with the data. And I also need to iterate through the child records, for each supply model, for example the NumberedInventories and DoStuff with that as well.
I need help doing this in VB rather than C# if possible. I am not looking for the whole solution...if you can supply a couple of code-snippets to get me on my way that would be great.
Thanks for your help.
EDIT
For the record I have already written the following code...Dim _dataContext As DataContext = New DataContext(ConnectionStrings("SupplyModelDB").ConnectionString)
Dim SMs As Table(Of Data.SupplyModels) = _dataContext.GetTable(Of Data.SupplyModels)()
Dim query = From sm In SMs Where sm.SupplyModelID = 1 Select sm
This code is working...I have a que开发者_Go百科ry object and I can use ObjectDumper to enumerate and dump the data...but I still can't figure it out...because ObjectDumper uses reflection and other language constructs I don't get. It DOES enumerate both the parent and child data just like I want (when level=2).
PLEASE HELP...I'M stuck. Help!
Seth
in C# it would be:
var result = from s in _dataContent.SupplyModels where s.SupplyModelID==1 select s;
foreach(SupplyModel item in result)
{
// do stuff
foreach(SupplyModelChild child in item.SupplyModelChilds)
{
//do more stuff on the child
}
}
and a VB.NET version (from the Telerik code converter)
Dim result As var = From s In _dataContent.SupplyModels _
Where s.SupplyModelID = 1 _
Select s
For Each item As SupplyModel In result
' do stuff
'do more stuff on the child
For Each child As SupplyModelChild In item.SupplyModelChilds
Next
Next
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