if users press the browser's back button to reach the prior page, the page should display a message like "web page expired".
can i use javascript for this???
for example:
there are 4 pages in web sites. on page 1,2 and 3 the user can use the back-button, wheras on the 4th page the user gets the desired message.
i thought that i can do this by using counter.
i used following javascript on the master page ..
<script type="text/javascript">
function GoBack() {
window.history.go(+1);
}
</script>
and call the function in body like this:
<body onload="GoBack();">
and on the 4th page_load i do the following:
Response.Cache.SetCacheability(HttpCacheability.NoCache);
it is working for all pages .. but i want to do this only for the 4th page
If you only want it on that page level, and when you use postbacks, then I suggest you simply keep it in ViewState instead of Session state. Session's also still available on other pages, where you might want to have other counters.
You need to keep the variable alive across requests. So one way is to put it in some viewstate or sessionstate. Sessionstate is least preferred. But you can possibly put it in a hidden textbox in the page and simply use it.
Looking at the problem after the much awaited update/edit, I shall suggest you to use SessionState. Please give a try on it.
Related
If I have a button on my ASP.NET page which will take you to another page but that page will do something and then will send user back using
Uri uu= Request.UrlReferrer;
if (uu!= null)
Response.Redirect(uu.ToString());
Now Which page event can I use so that when other pages displays I can display a message box.
In short I am running my custom code in a "aspx" page where user is directed on button click, and then after custom code I am sending user back to old page, but it happens so quickly that user doesn't realize that he went on another page, now I want to display a message box after redirect on same page user started from, what to do :S !
More Information
EDIT
Sorry guys but I can't make changes to ASP page where button is at all
:(
I'm a bit unsure about how the Request.UrlReferrer gets set. I think it's a browser implementation detail. So I wouldn't trust on that.
I would go for something like
A.aspx -> Redirects to -> B.aspx
B.aspx -> Redirects to -> B.aspx?message=1
And check if message=1 is set.
But if you want to use the Request.UrlReferrer it should be accessible on Page_Load
If you use it this way, it'll never appear to the client.
Maybe try redirecting back using javascript with a delay so user can be informed
The best thing to do it's add a flag to the redirected page so you can show something special when the flag is turned on
Uri uu= Request.UrlReferrer;
if (uu!= null)
Response.Redirect(uu.ToString() + "?Message=DataHasChanged");
and then in the ASP page
<% if (Request.QueryString["Message"] == "DataHasChanged") { %>
<div class="alert">The data has changed. Please review it or whatever</div>
<% } %>
I have two pages in ASP.NET 3.5 and I need to access/read the web controls values from the first page but on the second page. The second page is being displayed with a single link, there is not a post event or something like that.
I guess I should use ViewState but it looks so complicated for this task so please let me know a better way to achieve this.
P.S I'm using C# and Visual Studio 2010
If I understand correctly you have two .aspx pages and you want one page to share information with the other page. Does the first page link to the second page?
I ask because there are a couple of approaches you could take. You could add parameters to a query string in the link to the second page with the information you are trying to send. You could also use the session to temporarily store the information.
For example:
<asp:HyperLink NavigateUrl="www.<yoursite>.com/firstpage.aspx?eggs=1&bacon=yum" Text="Awesome Site" runat="server" />
In the second page you would have this in the codebehind in the Page_Load
string eggs = Request.QueryString["eggs"];
string bacon = Request.QueryString["bacon"];
Now you have the value from page one available in page two.
Another approach might be to use the Session like so:
Page one:
Session["bacon"] = "Yum";
Page two:
string bacon = (string)Session["bacon"];
However, I would advise against overusing session to pass information between pages.
Quick & "Dirty": A session variable which holds the info to pass.
On the first page:
Session["ValueToPassToOtherControl"] = "The value";
On the second page:
var value = Session["ValueToPassToOtherControl"];
Elegant: You need to manage your state in any way (via a static manager whose function is to store and retrieve that info, but that will be also variables). Problem is HTTP is stateless. So you need to bypass this limitation via some kind of storing and retrieving of the data.
You suggested the use of ViewState but forget it, ViewState is the technique used by an ASP.NET Web page to persist changes to the state of a Web Form across postbacks which isn't what's happening on your scenario.
There is a better way that using the QueryString jugglery and Session values.
You could just use the previous page property that is set during cross page posting.
Use an asp link button:
<asp:LinkButton runat="server" id="myLink"
NavigateUrl="~/Page2.aspx"
target="_blank" Text="Go to page 2"></asp:LinkButton>
Then on Page2.aspx.cs:
Get the values from the Page.PreviousPage as follows:
TextBox txtUser = (TextBox)Page.PreviousPage.FindControl("txtUser");
TextBox txtSomeValue = (TextBox)Page.PreviousPage.FindControl("txtSomeValue");
Use these as you require in your second page.
I googled this about 1/2 a hour no hit's. Scenario is that, dynamic scripts are saved in string builder whose "string" representation is stored in session. It just happens that when user navigates away from one page to another the script[from session] gets registered using "RegisterStartupScript". The script is registered in PreRender event of the Page. So i would like to clear this script in session while the page navigates away btw rule out a option to create another session variable and clear previous one. It's a overhead :(
Why are you storing this in Session, do you need to maintain this script in between GET requests?
If only postbacks are relevant you could store it in viewstate as this is maintained only when doing a postback.
If you want this string to be available on GET requests too you might want to introduce a different variable which has an identifier identifying the page for which the script is generated. If the requested page doesn't match the control variable you will have to generate a new script.
How is the user navigating away from the page? Can't you use an ASP.NET button instead of a hyperlink, and then do a Redirect in code once you have cleared your session variable?
protected void btnDoSomething_Click(object sender, EventArgs e)
{
Session["Value"] = String.Empty;
Response.Redirect(strURL, false);
}
OR You could add a variable in the query string and check it in the Page_Load event of the target page:
Webform1.aspx?reset=true
Since I cant comment yet, use onUnload().
It fires on full postbacks too. Ajax postbacks dont fire!
What you need to do, is guaranty inside the onUload function that you only clear the session when you want. Like setting a variable isPostBack to true before the postbacks so onUnload sees the variable and doenst send a request to clear the session.
You may use the JavaScript onUnload() and call an AJAX service, that will clear the server side session.
I have an ASP.NET page with one control (.ascx) on it. The page (.aspx) onload assigns some text to a couple labels and passes a product ID to the .ascx control. The .ascx control, onload, takes that product ID from the .aspx page and hits the database several times, does several calculations, etc - basically takes a long time to load.
So when I'm clicking a link to this .aspx page, it is taking 7-10 seconds for the page to load. I've narrowed it down to the calculations on the .ascx control being the culprit and I've optimized the code as much as I can ... but it's still taking too long.
Is there a way to load the .aspx page BEFORE the control loads? (Maybe display a "Loading..." animation? Like used in an UpdateProgress?)
You could do this with an UpdatePanel. It will take a little trickery, but try something like this:
1) Put the UserControl in an UpdatePanel.
2) Put a public property on your usercontrol like IsEnabled that it will use to conditionally do nothing or render a "please wait." Set it false from your main page.
3) Add some code in OnInit to your main page:
if (MyScriptManager.IsInAsyncPostback) {
MyUserControl.IsEnabled=true;
}
4) Add a client script along these lines:
finished=false;
Sys.WebForms.PageRequestManager.pageLoaded(function(sender,args) {
if (!finished) {
finished=true;
__doPostBack('','');
// you can include the uniqueID of your updatepanel as the first arg
// otherwise it will refresh all update panels
}
});
or with jquery..
finished=false;
$(document).ready(function() {
if (!finished) {...
}
});
What this should do is cause an async postback to be initiated immediately after the page is done loading, which will in turn cause the update panel to be refreshed. Since you set it to be enabled when it's in an async postback, it will render itself the 2nd time.
The only possible way to achieve this is by setting it up as a separate HTTP resource. At the moment .NET is integrating the control into the page so that it is waiting unti it has everything it needs to respond.
You could do this a multitude of different ways:
Web Service that gets called via javascript
Seperate page which contains the control (and is hosted within an iFrame to appear to be on the same page)
The best way to do this would be to use an iFrame (or something similar) which will instruct the browser to request the control after the main page has been sent).
Personally, I would never use an iFrame to load content on a page - that's more like a hack than anything and plus, iframe == "bad".
But they are right, you won't be able to do anything like what you're looking for.
If the user control DOES NOT have any web controls that cause a postback (or have any form controls that you need to access during a postback), then I would use AJAX to request the data on the server after the page has already loaded and use javascript to display the content on the page.
I am using jQuery to simulate a popup, where the user will select a series of filters, which I hope to use to rebind a ListView in the original window.
The "popup" is opened via an ajax request and the content is actually a diferent aspx file (the rendered output is injected into a div that acts as the popup).
I have another ListView in this popup, and it has pagination.
My problem is that since the popup is in reality html content inside a div in the same page, when I try to paginate, the whole page postbacks and is replaced with the aspx that has the filters.
How can I fix this?
I tried using an update panel to contain the ListView but it didn't work.
$("div.yourthingie").hide();
Will hide the part you want to show :) Instead of generating the popup on the fly, leave a small part already made, and hide it in the begining, when you need to show, unhide and add the information you need to.
Hope it helps
Either get rid of the HTML "crust" and just produce the <div> with its contents, or use an IFRAME.
First, let's think through what is happening. When you submit the original page, you are taking a "normal" Request/Response trip to get the code. On the page is a JQuery AJAX bit that fires off what is essentially a modal dialog. The desired effect is the user plays with the new page until they have figured out their filters and submits back. The problem is this "modal page" loses information when someone paginates.
The solution to this is fairly simple, in theory. You have to store the "filters" in the popped up page so they can be resent, along with pagination information. OR you have to cache the result set while the user paginates.
What I would do to solve this is create a static page that has the "filters" in place and work out the AJAX kinks separate from having the page post back to a parent page. Once you have all of the AJAX bits working properly, I would then link it into the popup routine and make sure the pagination is still non-problematic. THe final problem is creating a JavaScript routine that sends back to the parent page and allows the parent page to send its JQuery bits back to the server.
I am not sure about the HTML DIV part of the equation and I think you can solve the problem without this solution. In fact, I believe you can make the "modal popup" page without invoking AJAX, if it is possible to either a) submit the filters to apply via the querystring or b) fake a form submit to the second page. The query string is an easier option, but it exposes some info. Faking a form submit is not that difficult, overall, but could be problematic with a popup.
I am just firing off some ideas, but I hope it spurs something for you.