I've got a user list on the left side of my page in a datagrid and I want to load a div in the right side of my page with the clicked user's information. I assume I'll do the load of the div in the itemcommand event, but how do I handle page load then? Do I need to know what caused the postback? Do I need to reload the grid on page_load as well?
how do I handle page load then?
Every postback uses a brand new instance of your page class, and completely rebuilds the page. The only thing that's different is that some controls might be pre-populated via ViewState. You don't need to repeat the load work for any of those controls.
Do I need to know what caused the postback?
ASP.Net will handle that for you and fire the event. You only need know whether it is a postback, and maybe not even that (see the next part).
Do I need to reload the grid on page_load as well?
Yes. Well, sort of. You need to re-render the html for the grid to the browser. The good news is odds are your grid data is already in viewstate and it will happen automatically. You don't need to worry about it yourself.
However, in many cases you may find that it's better to turn off viewstate for grids and reload them on each postback anyway. This is because ViewState is just a hidden input on your page that must be posted (uploaded) to the server with each request. Most internet users have very limited upload bandwidth, and so a large ViewState can make your site seem slugish, even if your server is hardly breaking a sweat.
Depending on your situation, you might do better by trading some excess server performance for site responsiveness by disabling ViewState on select controls. In this case, you will always load the grid and no longer need care whether or not a request is a postback.
By contrast, if this is an intranet application where users typically have local ethernet connections to your web server it's hard to beat ViewState for balancing responsiveness and server performance.
Exclude the grid binding with checking !IsPostBack
if(!IsPostBack){
// Bind the Grid
}
For div itemcommand you get retrieve the value of which is clicked from grid and load the user's information.
So, you will not required to load the grid everytime. It will just load first time. I dont think you will required to check what cuased the postback, because anyway you will load grid once only.
Related
I have a page containing a large amount of controls that can trigger postbacks to the server. I know that it is not considered good practice to have a huge amount controls on one page, but the nature of my ASP.NET web application requires it. Seeing that I have a large amount of controls on this page, I make extensive use of UpdatePanels. I am storing ViewState in Session in order to reduce the response size of the page, which works beautifully.
However, with Fiddler I noticed that the 'asyncPostBackControlIDs' after the '__VIEWSTATE' part of the ajax response contains a list of every control of every UpdatePanel that can trigger a postback. This list is huge! It seems that this list doesn't change much per page, and thus it doesn't make sense to download the entire list every time a postback within an UpdatePanel occurs...
Is there any way to store the 'asyncPostBackControlIDs' on server like you can do with ViewState, or otherwise reduce the size of the 'asyncPostBackControlIDs' list?
AFAIK, there is no documented way for storing asyncPostBackControlIDs else where - further, I am very much in doubt if there can be such possibility because most probably those control ids would be required on client side to decide whether to do regular or asynchronous post-back.
You can set ChildrenAsTriggers property of UpdatePanel to false and register controls manually that are actually triggering the post-back - for example, you may have LinkButton/HyperLink that has java-script handler.
Further, perhaps you may able to reduce the list of controls that can cause post-back. For example, you can use anchors(a) instead of linkbuttons/hyperlinks and then set a hidden variable and then simulate a (hidden) button click. On server side, the value of hidden variable would indicate the actual control responsible for post-back. This way, you can have one button that is a post-back control for many other controls.
Finally, you are really a guy who want to have very efficient request/response streams then abandon ASP.NET control model and rather use ASP.NET MVC. Or at less scale, stop using Update Panels for AJAX (they do complete POST of page and almost entire page cycle is executed at server side) and use script services (along with jquery plugins) instead.
Lastly, you need to see the control ids size with the actual response size - for example, 5K long ids within 100K response may not be a large overhead. Reducing those ids would probably give you 5% savings (if possible) but are efforts for the same worth it?
This is 10KB in my HTML source:
<input type="hidden" name="__VIEWSTATE" id="__VIEWSTATE" value="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/>
This represents ~50% of the entire size of the page.
Why does it do this, why so long? Can I do anything about it? It's bad for mobile users.
What is this view state anyway and how to mitigate its size
In Asp.net WebForms every control saves its state because HTTP protocol is stateless and Asp.net WebForms pages bypass that by saving every control's state in this Base 64 encoded string. This is the only way for Asp.net framework to know whether some control's value has changed or not. But... This automatically means that static controls that don't get POSTed back to server (like label for instance) don't need to save their state. You can always set their EnableViewState="false".
Unfortunately this can't be set without any other code changes on other controls, that do get POSTed back (every server-side control that renders some sort of an input in HTML). This basically means that setting EnableViewState="false" on page level (within #Page directive) will have consequences that are seen as controls loosing their values, controls not firing certain events etc.
So, the more server-side controls you have the larger it will get (without turning it off on certain controls).
But I wouldn't worry if its size is 10k. That will go back and forth rather fast and painless. You will have problems when it gets much larger. I once worked on a project and we had an issue with a certain page (done by less experienced developer) where view state grew over 1MB. Imagine that. What a slowdown!
How to turn it off completely on page level
When you turn view state off on page level you have to be aware that certain controls that were loaded (or better said data bound) in on of your page's events, will have to be reloaded each time your page gets POSTed back at server. Otherwise they will show up as empty when your page gets back to the client.
Your server controls are filling the ViewState with data they will need on postback. If your page does not postback you can just disable the ViewState for the page.
To disable ViewState for the page you can just add EnableViewState="false" to the #Page directive. Please be aware you should only use this as a solution if you are 100% sure the page does not postback.
You also might want to check this MSDN article to get a better idea of what the ViewState does.
Disable viewstate for static controls, like a gridview.
Check out this question for more info:
If you are concerned about the viewstate on the client side, then think about storing it on the server side. Perhaps in a session variable. Take a look at this article as there is statistical comparison given. Download the solution and check out how to store it on the server side.
An Analysis of Keeping ViewState out of the Page
This article explained it neatly to me in the past: Taking a Bite Out of ASP.NET ViewState.
Basically viewstate's on by default and, depending on which controls you use, it can get out of hand pretty fast. Especially data controls like the gridview are responsible for massive injection of viewstate. You can disable that on a per control basis by setting the EnableViewState property to false. Be careful however as taking out viewstate might also take out functionality of the controls. So do it one by one and test test test.
Another way, and likely better for mobile, is to make use of ASP.NET MVC instead which doesn't have to deal with automatic viewstate injection.
I am working on a project which creates controls dynamically for a form in the page_load event, loads in their current values from the database and saves their values (using FindControl) when the user clicks the continue button.
When I added a control statically in the .aspx page and followed their same procedure of loading the value in the page load and saving it on the button press I found that the value would not save correctly. It seems that it wouldn't save because the click event fires after the page_load, so the page_load of the post back reverted the value and the user entered value was not saved.
The strange thing is that by changing the control to be dynamically created just as all the other controls on the page and keeping the loading and saving the same it now works. Even though the page load still creates the control with the old database value.
It seems like a very fundamental asp .net feature here but i'm just unclear as to what is going on. I suspect it is to do with the timing of creation and maybe when the view state kicks in.
Static page controls are created just like dynamic page controls. The difference might be coming in your Page_Load. Whenever you postback all the controls are created afresh which means they are created with their initial values. This happens because after creating the controls asp.net throws away the controls/objects.
So, when the request comes, the first thing that asp.net does it to recreate the controls by looking at their definitions (in the designer files). On each postback they are created and initialized again losing their state in the process.
But after creating the controls Asp.Net loads any viewstate that is sent along with the request which makes people think that the state is always saved at the server.
What might be happening is that either the viewstate is not enabled for your control (in case they are created in designer), in which case you may try using EnableViewState property to true of the control.
Or, when you're doing a Page_Load, you're forcefully re-initializing everything. And in process losing all the control data. If you could post the logic of Page_Load, it might get clarified.
Make sure that:
you are not setting the value again for the static control in Page_Load. The dynamic control are probably getting around it by grabbing the ViewState and form values at a different stage in the lifecycle.
The dynamic controls are added After the static control. Or at least they are added in a different container. Placement in the control's collection can affect the ViewState, although it doesn't look like your scenario / since what you mention seems to be more about the values in the current post.
The save is happening After the Page_Load in response to the corresponding event.
I've run into similar problems in the past (quite a few times actually), but what helped me the most is understanding the ASP.NET Page Lifecycle.
Microsoft has an article on it which describes it pretty well, but this post by Solomon Shaffer really cleared up everything.
I suggest reading them both and coming back with additional questions regarding to a particular state, when to load/save data etc..
Hope this helps.
Marko
Note that you may want to use Page.IsPostBack property to avoid reinitializing values on button clicks and other events.
private void Page_Load()
{
if (!this.IsPostBack)
{
// Assign values to the controls.
}
}
I have a very big problem. I am making a CRM (Costumer Relationship Management) System in ASP.NET 3.5
I have based my entire project on DevExpress.com controls and the use of UpdatePanels.
Now one of my pages, which is a central page in the whole system, contains a very big amount of possibilities and therefore a big amount of UserControls.
Now my problem is that it's getting really really slow because of the fact that UpdatePanels are reposting the entire page and not only the update panel. We are talking sometime 3-4 seconds before a popup window appears :(
Is there any way I can refactor this entire system away from UpdatePanels without breaking my neck?
Are there anyway I can optimize my use of UpdatePanels?
The ViewState is also absolutely giant.
Any good ideas are welcome...
There's no way to get around posting the entire page using UpdatePanels. In lieu of redesigning the app here are a couple things I'd try:
Disable viewstate for any controls that don't need it
Set the UpdateMode="Conditional" for your user controls. This won't get around posting the entire page but it will cut down on rendering time a little. Only the content for the specific UpdatePanel will be updated in the browser.
Make sure your user controls have short IDs. The way ASP.NET webforms names controls in the html these IDs get repeated quite a bit if you have a lot of server controls. Same goes for naming master page placeholders. I once cut a large page to half the size by renaming user controls and placeholders.
Since you're a DevExpress user, you might consider taking a little time to learn their CallbackPanel which will allow you to do asynchronous processing without the overhead of the UpdatePanel.
Alternatively (someone please correct me if I'm wrong) but if all of the postbacks are asynchronous (i.e. in an UpdatePanel), wouldn't it be theoretically possible to disable ViewState for the entire page (in the Page directive) without negative consequences? You'd have to test it completely off course, but it's worth a shot.
You'll have to replace some of the postbacks contained in your update panels with real AJAX calls, i.e. send only the data that is required for the action to the server and get back only what's required to update the view, getting rid of the postback and the UpdatePanels.
(You'll notice my use of the terms 'action' and 'view' - yes, I am an MVC fan. The situation you are in is typical of the mess that is easily got into using WebForms and the ASP.NET AJAX controls.)
I must be missing something. Why is your updatepanel is reloading the entire page. The point of an updatepanel is to refresh only what is in that panel, isn't it? Thanks for the explanation. I guess we're talking about reposting the page and not redrawing the panel as I thought.
Try turning off ViewState, especially for grids.
What kind of control is most common on your page? Try replacing those with your own lightweight UserControl or Server Control that does not use ViewState or ControlState
For all Interested I want to add a solution on how to get rid of the Viewstate data on clientside. It does give the server an extra load but if you are in the same situation as me and have a lot of server power and need to take the load of the clientside this is nice.
Let all your pages Derive from BasePage.cs looking like this
public class BasePage : System.Web.UI.Page
{
protected override void SavePageStateToPersistenceMedium(object viewState)
{
string vsKey = String.Format("VIEWSTATE_{0}_{1}_{2}", base.Session.SessionID, Request.RawUrl, DateTime.Now);
Session.Add(vsKey, viewState);
ClientScript.RegisterHiddenField("__VIEWSTATE_KEY", vsKey);
}
protected override object LoadPageStateFromPersistenceMedium()
{
string vsKey = Request.Form["__VIEWSTATE_KEY"];
return Session[vsKey];
}
}
Now you have a key to the viewstate data session instead of the viewstate in your code...
Works like a charm for me on a website with 1000-1200 daily visitors as well.
What choices do I have for creating stateful dynamic content in an ASP.Net web site?
Here's my scenario. I have a site that has multiple, nested content regions. The top level are actions tied to a functional area Catalog, Subscriptions, Settings.
When you click on the functional action, I want to dynamically add content specific to that action. For example, when Catalog is clicked, I want to display a tree with the catalog folders & files, and a region to the right for details.
When a user clicks on the tree, I want a context sensitive details to load in the details region (like properties or options to manage the files).
I started with UserControls. They worked fine as long as I kept loading everything into the page, and never let one disappear. As soon as one disappeared, ViewState for the page blew up because the view state tree was invalid.
(I didn't want to keep loading stuff into my page because I don't want the responses to be too huge)
So, my next approach was to replace my dynamic regions with IFrames. Then instead of instantiating a UserControl, I would just change the source on my IFrame. Since the contents of the IFrames were independent pages I didn't run into any ViewState problems.
But, I'm concerned that IFrames might be a bad design choice, but don't fully understand why. The site is not public, so search engines aren't a concern.
So, finally to my question.
What are my options for this scenario? If I choose an Ajax Solution (jQuery), will I have to maintain my own ViewState? Are there any other considerations I should take into account?
Controls that are added dynamically do not persist in viewstate, and this is the reason that it doesn't matter if you use AJAX or iframes or whatever.
One possible work-around is to re-populate controls on postback. The problem with this, is the page life-cycle (simplified) is:
Initialize
LoadViewState
Load Postback Data
Call control Load events
Call Load event
Call control events
Control PreRender
PreRender
SaveViewState
Unload
What this means is the only place to re-add your dynamic controls is Initialize -- otherwise posted data (or viewstate information) is not loaded into that control. But often, because Viewstat/postback data isn't available yet in Initialize, your code doesn't have the information it needs to figure out which controls need to be added.
The only other work-around I've found in this situation is to use a 3rd party control called DynamicControlsPlaceholder. This works quite well, and persists the control information in viewstate.
In your particular case, it doesn't seem like there are that many choices/cases. Is it practical just to have all the different sets of controls in the page, and put them inside of asp:placeholder controls, and then just set one to visible, depending on what is selected?
Some other options:
Content only appears to be dynamic. You load enough controls on the page to handle anything and only actually show what you need. This saves a lot of hassle messing with view state and such, but means your page has a bigger footprint.
Add controls to the page dynamically. You've already been playing with this, so you've seen some of the issues here. Just remember that the place to create your dynamic controls for postbacks is in the Page_Init() event, and that if you want them to be stateful, you need to keep that state somewhere. I recommend a database.
you've got a number of different options, and yes, IFrames were a bad design choice.
The first option is the AJAX solution. And with that there's not really a viewstate scenario, it's just you're passing data back and forth with the webserver, building the UI on the fly as needed.
The next option is to dynamically add the controls you need for a given post, everytime. The way this would work, is that at the start of the page life cycle, you'd need to rebuild the page exactly as it was sent out the last time, and then dump out all the unneeded controls, and build just those that want.
A third option would be to use Master pages. Your top level content could be on the Master page itself, and have links to various pages within the website.
I'm sure given enough time, I could come up with more, but these 3 appeared just from reading your problem.
dynamic controls and viewstate don't mix well, as noted above - but that is a Good Thing, because even if they did the viewstate for a complex dynamic page would get so bloated that performance would diminish to nil
use Ajax [I like AJAX PRO because it is very simple to use] and manage the page state yourself [in session, database tables, or whatever works for your scenario]. This will be a bit more complicated to get going, but the results will be efficient and responsive: each page can update only what needs to change, and you won't be blowing a giant viewstate string back and forth all the time