Learn how to a build a cloud-first strategyRegister Now

x
?
Solved

how to access listview value on delete command

Posted on 2014-01-29
6
Medium Priority
?
516 Views
Last Modified: 2014-01-30
I would like to ask for help regarding an asp page with a list view.

I want to get the Id value for the selected row, so that I can query the entity framework, get the record and delete it.

Down below is the code for when I do the e.Command = "Delete"
        If e.CommandName = "Delete" Then

            Dim myContext As New OLTPEntities
            Dim myRecipeStepsHistory = myContext.RefineRecipeStep.Where("it.Recipe_Id=" & Me.lvRecipeSteps.FindControl("Recipe_Id").ToString())
            Dim strRefineRecipeStepRecord = New StringBuilder("")

            If Not IsNothing(myRecipeStepsHistory) Then
                ' Recipe_Id
                strRefineRecipeStepRecord.Append("Recipe_Id: " & Me.lvRecipeSteps.FindControl("Recipe_Id").ToString() & ", ")

Open in new window

I get an Object reference not set to an instance of an object, message.

Dim myRecipeStepsHistory = myContext.RefineRecipeStep.Where("it.Recipe_Id=" & Me.lvRecipeSteps.FindControl("Recipe_Id").ToString())  << this line, I thinkis because I am not looking for the right control?

I have attached a copy of my aspx code. Hopefully some one will be able to provide guidance on this problem.

Thank you much.
listview-aspx-code.txt
0
Comment
Question by:metropia
  • 3
  • 2
6 Comments
 
LVL 52

Expert Comment

by:Carl Tawn
ID: 39818149
What event are you using to do the delete? The ListView Deleting event passes a Keys collection as part of it EventArgs. That collection will include the ID of the row being deleted.
0
 

Author Comment

by:metropia
ID: 39818189
I started using:
Private Sub lvRecipeSteps_ItemCommand(sender As Object, e As ListViewCommandEventArgs) Handles lvRecipeSteps.ItemCommand

Open in new window

And then check the Command Name:
If e.CommandName = "Delete"

Open in new window

I now changed the code to use ItemDeleting event, because I have a DataKeyNames="Id"
defined, but I have not been able to figure out how to access it and then query the Entities.
Private Sub lvRecipeSteps_ItemDeleting(sender As Object, e As ListViewDeleteEventArgs) Handles lvRecipeSteps.ItemDeleting
Dim myContext As New OLTPEntities
Dim myRefineRecipeSteps = myContext.RefineRecipeStep.Where("it.Id=" & Me.lvRecipeSteps.DataKeys().ToString())   << this does not work

Open in new window

0
 

Author Comment

by:metropia
ID: 39818277
I am still not able to make it work. I hope you can offer some help.

I really need it.

Thank you
0
Efficient way to get backups off site to Azure

This user guide provides instructions on how to deploy and configure both a StoneFly Scale Out NAS Enterprise Cloud Drive virtual machine and Veeam Cloud Connect in the Microsoft Azure Cloud.

 

Author Comment

by:metropia
ID: 39818301
This is my current code and my error.

screen shot error - current
0
 
LVL 52

Assisted Solution

by:Carl Tawn
Carl Tawn earned 1000 total points
ID: 39820297
You don't need to cast the data key to a textbox. Try:
Dim myRefineRecipeSteps = myContext.RefineRecipeStep.Where("it.Id=" & currentDataKey.Value).FirstOrDefault()

Open in new window

0
 
LVL 83

Accepted Solution

by:
CodeCruiser earned 1000 total points
ID: 39820508
Try changing

Dim myRefineRecipeSteps = myContext.RefineRecipeStep.Where("it.Id=" & Me.lvRecipeSteps.DataKeys().ToString())


to

Dim myRefineRecipeSteps = myContext.RefineRecipeStep.Where("it.Id=" & e.Keys("ID"))
0

Featured Post

Free Tool: Site Down Detector

Helpful to verify reports of your own downtime, or to double check a downed website you are trying to access.

One of a set of tools we are providing to everyone as a way of saying thank you for being a part of the community.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

In real business world data are crucial and sometimes data are shared among different information systems. Hence, an agreeable file transfer protocol need to be established.
Simulator games are perfect for generating sample realistic data streams, especially for learning data analysis. It is even useful for demoing offerings such as Azure stream analytics, PowerBI etc.
We’ve all felt that sense of false security before—locking down external access to a database or component and feeling like we’ve done all we need to do to secure company data. But that feeling is fleeting. Attacks these days can happen in many w…
Are you ready to place your question in front of subject-matter experts for more timely responses? With the release of Priority Question, Premium Members, Team Accounts and Qualified Experts can now identify the emergent level of their issue, signal…
Suggested Courses

810 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question