[2 days left] What’s wrong with your cloud strategy? Learn why multicloud solutions matter with Nimble Storage.Register Now

x
?
Solved

Viewstate of DataGrid CheckBox control...

Posted on 2006-10-25
10
Medium Priority
?
615 Views
Last Modified: 2008-01-16
Hi,

I am programmatically adding a checkbox control to my datagrid column (.net 1.1).

What I need to do is capture whether or not it is being checked on postback.

So in an ItemDataBound event I have:

If e.Item.ItemType = ListItemType.Item Or e.Item.ItemType = ListItemType.AlternatingItem Then
            Dim chkSelected As CheckBox
            chkSelected = e.Item.FindControl("ChkSelection")

            If chkSelected.Checked Then
                            System.Diagnostics.Debug.WriteLne("Testing")
            End If
End If

 Problem is that the checkbox is always testing as being unchecked - I assume that this is because after postback the checkbox is recreated and it's viewstate has not been saved?!

Does anyone know of a workaround?

thanks

KS
0
Comment
Question by:Ramesh Srinivas
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 5
  • 3
  • 2
10 Comments
 
LVL 96

Accepted Solution

by:
Bob Learned earned 2000 total points
ID: 17805595
If you are binding the DataGrid to a Datasource, and you aren't binding the CheckBox to a value, when then page posts back, that value isn't saved, unless you handle persisting the ViewState yourself.

Bob
0
 
LVL 6

Expert Comment

by:Roopesh_7
ID: 17807533
save the things in to hidden variable.... then reassign it on load
0
 
LVL 11

Author Comment

by:Ramesh Srinivas
ID: 17810419
TheLearnedOne ,

When you say bind value to checkbox, you mean that I should set it to true or false?

How can I persist the viewstate myself?

What would be the easiest way?

Roopesh,

I dont understand what you mean, can you provide more detail please.


thx,

KS
0
Concerto Cloud for Software Providers & ISVs

Can Concerto Cloud Services help you focus on evolving your application offerings, while delivering the best cloud experience to your customers? From DevOps to revenue models and customer support, the answer is yes!

Learn how Concerto can help you.

 
LVL 96

Expert Comment

by:Bob Learned
ID: 17811042
No, I mean if you are binding to a DataTable, then you should have a boolean column that stores the value of the CheckBox, and bind the DataGrid column to that boolean column.

Bob
0
 
LVL 11

Author Comment

by:Ramesh Srinivas
ID: 17812532
Ok, I will have to bind a column to the checkboxes.

When I check the boxes in the grid, a postback occurs - in which event can I check the state of checkboxes?

Is it possible to add an indexchanged event handler for each checkbox in the grid?

thank you,

KS
0
 
LVL 11

Author Comment

by:Ramesh Srinivas
ID: 17812696
Basically, when the state of any checkbox changes, I want to call a custom procedure.

thanks,

KS
0
 
LVL 6

Expert Comment

by:Roopesh_7
ID: 17813112
if u need to post back the form during check box checked call a javascript
create a hidden variable ,
function inside that javascript
change the value of hidden variable.then submit the form
document.formname.submit();

during load check the value of hidden variable and call the function
0
 
LVL 11

Author Comment

by:Ramesh Srinivas
ID: 17817797
Roopesh,

My page already postbacks when I tick a checkbox, but I want to be able to run a custom procedure on postback.

I cannot check the state of the checkbox in the ItemDataBound event as it only fires when the data changes.

regards,

KS
0
 
LVL 96

Expert Comment

by:Bob Learned
ID: 17818499
You can add an event handler in the ItemCreated event handler.

Bob
0
 
LVL 11

Author Comment

by:Ramesh Srinivas
ID: 17818977
Well I created an CheckChanged event in my custom template class and it works great.

The parameter I needed to pass to my custom procedure was the DataKeyField of the grid which I acquired like so:

Dim theGrid As DataGrid = CType(container.Page.FindControl("DataGrid1"), DataGrid)
Dim theID As Integer = CType(theGrid.DataKeys.Item(container.ItemIndex), Integer)

Dont know if thats the most efficient way to do it - but hey, it works!

Thanks.

LearnedOne, I give the points to you as you pointed out that I needed to bind a column from a datasource to my checkbox template column - that solved the initial state problem.

thanks all,

KS
0

Featured Post

Industry Leaders: We Want Your Opinion!

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

Question has a verified solution.

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

User art_snob (http://www.experts-exchange.com/M_6114203.html) encountered strange behavior of Android Web browser on his Mobile Web site. It took a while to find the true cause. It happens so, that the Android Web browser (at least up to OS ver. 2.…
International Data Corporation (IDC) prognosticates that before the current the year gets over disbursing on IT framework products to be sent in cloud environs will be $37.1B.
In this video you will find out how to export Office 365 mailboxes using the built in eDiscovery tool. Bear in mind that although this method might be useful in some cases, using PST files as Office 365 backup is troublesome in a long run (more on t…
This lesson discusses how to use a Mainform + Subforms in Microsoft Access to find and enter data for payments on orders. The sample data comes from a custom shop that builds and sells movable storage structures that are delivered to your property. …

656 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