Thinking out loud here Here's something I never noticed before: It looks like an ASP.NET Repeater doesn't fire OnItemCommand events when ViewState is off for the control. Not sure why this should be, but I'm working on a form where there are several repeaters all of which are reloaded on every.I have a LinkButton control in the Repeater template with a CommandName and CommandArgument set like this: <% # Eval( 'Title' )% <% # Eval( 'Entered' )% <% # Eval( 'Abstract' )%With ViewState on, all works fine. Turn ViewState off and the OnItemCommand event is never fired.I haven't noticed this before because in most apps I tend to use old school links instead (ie. Horses: You are right in saying that a different LinkButton in a different row may raise the event. That's part of the reason why you use the CommandName/CommandArgument instead of relying on an index.Ofcourse, this would fail when you clicked on say the link of the second item, and when you postback there is only 1 item left (because someone else removed an item). It would fail because the Page will be unable to find the clicked control, because it is no longer re-created by the Repeater.Instead of disabling the ViewState on the Repeater, you might want to try and disable the viewstate of all child controls instead (eg. Place them in a PlaceHolder and disable it's ViewState).
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In that case the Repeater will re-create the items on a postback, and the events should raise as expected. You should then be able to re-bind in the PreRender phase (ofcourse, make sure you always rebind in the PreRender). Keeping the ViewState of the Repeater itself enabled should not be an issue, since I believe all it stores in the ViewState is the item count.
In my opinion, this item count should really be stored in the ControlState instead, for exactly this scenario. If it would be part of the ControlState, you could simply disable the ViewState on the Repeater.
I am having a really weird day. I tried to move a site from 1.1 to 2.0 and it basically worked, until I noticed that linkbuttons in a datagrid (not a gridview) did not keep their commandargument and commandname properties on postback.The code is a simple datagrid with a template column that has a linkbutton and the CommandArgument, CommandName, Text and Enabled properties are set as '<%# Bind('stuff')%'.I have no idea what is going on!I mean, it goes into the onItemCommand or onClick or whatever, it does show the correct control as e.CommandSource, but the CommandArgument and CommandName properties are empty. The Text or Enabled properties are both ok.ViewState is ON on the page, on the Datagrid and even on the linkbutton.
If I replace the LinkButton with a Button the same thing happends. OK-this is an ancient post. But I ran into exactly the same thing this morning on a SharePoint project using SmartPart and lots of other 'stuff'. That is-setting up ItemCommand on a simple repeater just didn't freakin' fire.After.much. experimentation (viewstate on, viewstate off, checking eventtarget, doing unique ID lookup at page load to manually fire event, and much more) here was the skinny-it wasn't viewstate at all. Rather, the stupid repeater control is (apparently) reloading the control set after my initial data bind.This is still (I'm sure) some silly interaction between SP and viewstate, but here's the timeline:1. SmartPart hosts ASCX control.2.
My hosted ASCX control is a tabbed page, so I dynaload the tab pages (if I'm not in page editing mode).3. In my dynaloaded tab page, in OnInit I do a databind. (I have to do this regardless of viewstate, I suspect it's an artifact of me adding controls to the page dynamically.)4.
All the normal databinding fires on my repeater. The RepeaterItem (rows) objects all have auto-generated IDs. (Hint: That's the real problem.)5. Check on the generated source and I see that the unique IDs being created for the LinkButton elements show a.different. unique ID for the RepeaterItem. That is-when the first RepeaterItem was initially created during my explicit data bind its name was 'ctl01'.
The LinkButton's unique ID should be '.$ctl01$lnkbtn'. However, on the generated source I see '.$ctl06.lnkbtn'. There are three repeater items-I believe what's happening is that (somewhere!) my explicitly-generated three rows are being replaced and new RepeaterItem entries being created-three times!The problem was this-because at PageLoad time the.current. generated unique ID for the link button on, say, row 3 is.different. than the unique ID being passed as EVENTTARGET.
So ASP.NET can't match the control IDs, so the event doesn't fire. To hack around this problem: a) Created class variable int itemNumber.
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B) Override repeater's DataBinding and set itemNumber to zero. C) Override ItemCreated and set the e.Item.ID to 'c' + itemNumber.The net effect is that regardless of how many times my repeater items (rows) are (re)created, they will always have the same ID. On checking the UniqueID in the page source I see that each of my three link buttons have '.$c1$lnkbtn' '.$c2$lnkbtn' and '.$c3$lnkbtn' respectively. On PageLoad I see that EVENTTARGET has that UniqueID properly set. And since ASP.NET can now match up EVENTTARGET to a real-honest-to-goodness LinkButton I see that everything is A-OK (including receiving CommandName and CommandArgmument as part of ItemCommand event args).Moral-1. Understand why ASP.NET is 'recreating' my repeater rows (nope, don't know that one yet). So better moral-2.
Go out of your way to make sure that IDs for dynamic controls are always created properly (that is, set the ID explicitly if you possibly can). Things just tend to work better. I am experiencing similar problems since I upgraded to 3.5 sp1.
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In a Datalist, after the linkbutton OR imagebutton is clicked, the itemcommand even is not fired - the view state appears empty - even though enableviewstate = true.The same code works perfectly in 2.0 - appararently with 3.5 sp1, there is an update for 2.0 also which breaks my code.Does anyone understand what might have changed and how I can get the itemcommand firing around with 3.5 sp1?Please post comments here and email me if possible (matt.at. This is one of the most interesting threads. Hope, I can shed some light on the process. (.Net 3.5 SP1)I'm working on the page where GridView is dynamically created and it has one of the columns as ImageButtons with CommandArgument used to pass PK of the record. So, I found that in my case I have to recreate GridView object with exactly the same ID and set of rows (emty ones do just fine) in order to get gridRowCommand event fired with correct command argument.
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It looks like.Net runtime needs the rows to match automatically generated control ID for the clicked button and then it uses ViewState to pass the CommandArgument value. It actually passes CommandArgument values for every row but only one which was clicked is used. It determines which one was clicked by looking at the Request.Form collection.So, if I re- create my dynamic grid with correct number of rows but set EnableViewState for the whole page to false the event gets fired but the CommandArgument is null as it wasn't passed around.