I think this must be a common scenario-- but I can't seem to find a solution.
JQueryMobile site with authentication functionality:
Link on all pages takes user to dynamically loaded authentication page
All pages have back button functionality
A bad username and password causes an ajax form submission
Clicking the back button in this scenario takes you back to the authentication page (which makes sense because that's where you came from-- but if I input a bad password five times, I have to click on the back button five times before I get back to where I came from)
I guess what I want is to have the ajax form submission for logging in taken out of the "hash" history.
One way to solve this would be by keeping track of the failed attempts numberOfAttempts++. Then using history.go(-numberOfAttempts); when the back button is clicked.
Knocked-out a simple jQuery Mobile site with [logon -> index -> content] pages.
If I use the back button to the logon page, I can't escape no matter what I do - forward, back, filling it in, nothing.
I'd like to remove the #logon page from the navigation, so you cannot get back to it without typing it in, or logging out - any advice?
Easiest way to keep a page from showing up in history (with jquery mobile) is show that page in a dialog. This model works particularly well in situations where the content that would be in a dialog is either tangential to the main content or some sort of interrupt (which the login process is). See an example here. DISLAIMER: this is not the right way to implement content like this in the long run, it is only meant to show the effect of using a dialog in a login process to bypass insertion into history.
Another (more manual) route would be to use the a normal jqm page and do your login by way of an ajax posting. If the response came back as successful, then use location.replace() to remove the the current (logon) page from history.
I ended up removing the ajax navigation full stop and sticking to manual, not as pretty but headaches avoided!
i have created a MVC application , without using asp.net membership provider, i want to redirect the user to the login page if the user logged out and press back button from explorer.
Thanks
You can't do this, as the page the user see when clicking 'back' is in fact the cached version of the page.
The best you can do is request the browser to not cache logged in pages, to do this you would place:
Response.Cache.SetCacheability(HttpCacheability.NoCache);
on all pages you consider shouldn't be 'back button' accessible.
This is only a request however, browsers are under no obligation to oblige.
Now i can think in two solutions, you could create a filter for your controller, and control to authentication by Session, Cookies, etc... (what I don't recommend)
Sample of Actions Filters http://www.asp.net/mvc/tutorials/understanding-action-filters-cs
Second one and the best in my opinion, I preffer to do something more simple for Authentication, like Forms Authentication... take a look at this link:
http://weblogs.asp.net/fredriknormen/archive/2008/02/07/asp-net-mvc-framework-using-forms-authentication.aspx
I use this approach in my projects and works fine! Simple and easy!
I don't like very much of Membership provider.
I hope it help you!
PS: sorry for my english!
I'm new to mvc so I don't know if there is a trick to this or not. When a user runs a search on a site I'm building and I take them to the results page, if I click the back button the search form is empty. Is there some way to keep the form fields populated as they were when going back (without resorting to session)? Thanks.
Strange.
Fields should be there by default. What browser are you using?
If you're using a regular browser, then maybe your doing something weird, like, resetting the fields via JavaScript or something. Perhaps elaborating more on your current implementation would help diagnosing your problem?
A last solution would be saving the fields as a cookie and loading them via JavaScript on the forms page inside onLoad.
I'm making my way into web development and have seen the word postback thrown around. Coming from a non-web based background, what does a new web developer have to know about postbacks? (i.e. what are they and when do they arise?)
Any more information you'd like to share to help a newbie in the web world be aware of postbacks would be most greatly appreciated.
The following is aimed at beginners to ASP.Net...
When does it happen?
A postback originates from the client browser. Usually one of the controls on the page will be manipulated by the user (a button clicked or dropdown changed, etc), and this control will initiate a postback. The state of this control, plus all other controls on the page,(known as the View State) is Posted Back to the web server.
What happens?
Most commonly the postback causes the web server to create an instance of the code behind class of the page that initiated the postback. This page object is then executed within the normal page lifecycle with a slight difference (see below). If you do not redirect the user specifically to another page somewhere during the page lifecycle, the final result of the postback will be the same page displayed to the user again, and then another postback could happen, and so on.
Why does it happen?
The web application is running on the web server. In order to process the user’s response, cause the application state to change, or move to a different page, you need to get some code to execute on the web server. The only way to achieve this is to collect up all the information that the user is currently working on and send it all back to the server.
Some things for a beginner to note are...
The state of the controls on the posting back page are available within the context. This will allow you to manipulate the page controls or redirect to another page based on the information there.
Controls on a web form have events, and therefore event handlers, just like any other controls. The initialisation part of the page lifecycle will execute before the event handler of the control that caused the post back. Therefore the code in the page’s Init and Load event handler will execute before the code in the event handler for the button that the user clicked.
The value of the “Page.IsPostBack” property will be set to “true” when the page is executing after a postback, and “false” otherwise.
Technologies like Ajax and MVC have changed the way postbacks work.
From wikipedia:
A Postback is an action taken by an
interactive webpage, when the entire
page and its contents are sent to the
server for processing some information
and then, the server posts the same
page back to the browser.
Expanding on the definitions given, the most important thing you need to know as a web-developer is that NO STATE IS SAVED between postbacks. There are ways to retain state, such as the Session or Viewstate collections in ASP.NET, but as a rule of thumb write your programs where you can recreate your state on every postback.
This is probably the biggest difference between desktop and web-based application programming, and took me months to learn to the point where I was instinctively writing this way.
Postback happens when a webpage posts its data back to the same script/dll/whatever that generated the page in the first place.
Example in C# (asp.net)
...
if (!IsPostback)
// generate form
else
process submitted data;
Web developement generally involves html pages that hold forms (<form> tags). Forms post to URLs. You can set a given form to post to any url you want to. A postback is when a form posts back to it's own page/url.
The term has special significance for ASP.Net WebForms developers, because it is the primary mechanism driving a lot of the behavior for a page — specifically 'event handling'. ASP.Net WebForms pages have exactly one server form which nearly always posts back to itself, and these postbacks trigger execution on the server of something called the Page Lifecycle.
The term is also used in web application development when interacting with 3rd party web-service APIs
Many APIs require both an interactive and non-interactive integration. Typically the interactive part is done using redirects (site 1 redirects a user to site 2, where they sign in, and are redirected back). The non-interactive part is done using a 'postback', or an HTTP POST from site 2's servers to site 1's servers.
When a script generates an html form and that form's action http POSTs back to the same form.
Postback is essentially when a form is submitted to the same page or script (.php .asp etc) as you are currently on to proccesses the data rather than sending you to a new page.
An example could be a page on a forum (viewpage.php), where you submit a comment and it is submitted to the same page (viewpage.php) and you would then see it with the new content added.
See: http://en.wikipedia.org/wiki/Postback
Postback refers to HTML forms. An HTML form has 2 methods: GET and POST. These methods determine how data is sent from the client via the form, to the server. A Postback is the action of POSTing back to the submitting page. In essence, it forms a complete circuit from the client, to the server, and back again.
A post back is anything that cause the page from the client's web browser to be pushed back to the server.
There's alot of info out there, search google for postbacks.
Most of the time, any ASP control will cause a post back (button/link click) but some don't unless you tell them to (checkbox/combobox)
Yet the question is answered accurately above, but just want to share my knowledge .
Postback is basically a property that we can use while doing some tasks that need us to manage the state of the page, that is either we have fired some event for e.g. a button click or if we have refreshed our page.
When our page loads for the very first time , that is if we have refreshed our page, at that time postback-property is false, and after that it becomes true.
if(!ispostback)
{
// do some task here
}
else
{
//do another task here
}
http://happycodng.blogspot.in/2013/09/concept-of-postback-in.html