Expiration Date alarm in lightswitch

Question

I've this code:

Private Sub StartUp_Created()
            ' Write your code here.
            Dim a = Me.DataWorkspace.ApplicationData.ItemReciept.Where(Function(o) o.QualityCertificates.OrderBy(Function(q) q.RetestDate).FirstOrDefault < Today.Add(TimeSpan.FromDays(30)))
            Dim b = a.Execute.Count

            Me.ShowMessageBox("you have:" + b.ToString + " matrials with retest date before:" + Today.Add(TimeSpan.FromDays(30)))
End Sub

It's to find if there are "receipt items" may be expire soon.

but, I got this error:

FirstOrDefault is not supported.

Then, I've changed the code to :

Private Sub StartUp_Created()
            ' Write your code here.
            Dim a = Me.DataWorkspace.ApplicationData.ItemReciept.Where(Function(o) o.QualityCertificates.OrderBy(Function(q) q.RetestDate).Any < Today.Add(TimeSpan.FromDays(30)))
            Dim b = a.Execute.Count

            Me.ShowMessageBox("you have:" + b.ToString + " matrials with retest date before:" + Today.Add(TimeSpan.FromDays(30)))
End Sub

and I got this error:

Operator '<' is not defined for types 'Boolean' and 'Date'.

______________________________________________

So, Can you help me to fix this ?

Answer 1

Please, can anyone help me ?????

I've posted here because I know there is someone can show me to the right code.

Answer 2

Should I post it in other forum ????

Answer 3

Based on your original code, although it doesn't compile, what I am able to understand is that you want a collection of ItemReceipts where the RetestDate of the earliest QualityCetificate is at most 30 days in the future. Or were you trying to achieve some other set of results.

Would you agree that you can think of it as "all ItemReceipt instances where the RetestDate of any QualityCertificate is at most 30 days in the future? These should return equivalent results. The code for this query would look like:

Dim futureDate As Date = Today.Add(TimeSpan.FromDays(30))
Dim a = Me.DataWorkspace.ApplicationData.ItemReciepts.Where(Function(o) o.QualityCertificates.Any(Function(q) q.RetestDate < futureDate))

---

Justin Anderson, LightSwitch Development Team

Answer 4

I've do what you did tell me.

But, when I hit F5 I get the error above .... Please help me .

Answer 5

What you can do is create a query off of the ItemReceipt entity and call that query from the Startup_Created method:

1. Right-click on ItemReceipt in Solution Explorer and select Add Query. Name the query to whatever you want (let's say it's called Query1).

2. Click on <QueryName>_PreprocessQuery method from the Write Code drop down of the query designer.

3. Write the query code here, e.g.:

Private Sub Query1_PreprocessQuery(ByRef query As System.Linq.IQueryable(Of LightSwitchApplication.ItemReciept))
    Dim futureDate As Date = Today.Add(TimeSpan.FromDays(30))
    query = query.Where(Function(o) o.QualityCertificates.Any(Function(q) q.RetestDate < futureDate))
End Sub

4. From the Startup_Created method, execute the query off of the ApplicationData property in the data workspace and use the results however you want (in the code you've provided, you are counting the results):

Private Sub Startup_Created()
    Dim b = Me.DataWorkspace.ApplicationData.Query1().Execute().Count()
End Sub

---

Justin Anderson, LightSwitch Development Team

Answer 6

It's worked finally.

Thank you very much Justin Anderson.

But, I have another question ... :)

I've created the following query :

and you can see the relationships here:

I want to get all the items that don't have any price ... So, I've create that query. But, when I create search screen and use the UnPricedItems query as screen data to know what items I have without prices, nothing happen, the search screen appears with no items in it ... but I've create an Item receipt without give any price for that item.

If you got it ... what should I do to fix that query ?

Answer 7

But, when I execute the query I got this error :

So, can anyone help me ?????? 

please, I need the solution ASAP.

Answer 8

Please, can anyone answer me ???

What should I do to fix the error ??

Answer 9

Please, help me to find the best solution for this query.

I need it ASAP.

B.R.

Answer 10

Try

= "Release"

instead of

 Is "Release"

Also change all your And to AndAlso

---

Like Yann Said : "If you found this post helpful, please "Vote as Helpful". If it actually answered your question, remember to "Mark as Answer". This will help people find the answers that they're looking for more quickly."

Answer 11

Still the same error .... :((

What should I do ?

Answer 12

??????

Answer 13

anyone here ???

Answer 14

help me please, I'm new in VS lightswitch.

Answer 15

No one will help me ??? :((((((

Answer 16

Please, can anyone help ASAP ????

I need that query, my project is not functioning right now. Because that query.

Answer 17

I did it , yeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeesssssssssss

Finally.

I've shared the solution here, to let anyone who face similar problem to fix it.