Is there any way to inform web site has been changed?one way is get all web page contex and compare it with previous contex!but Im looking for solution that notify web page changes without get page context!
The only way that you could tell a website had changed without accessing the content is for the website to notify you itself, through an API or RSS feed or similar mechanism.
Unless the site in question has a mechanism to actively notify you...
You don't necessarily need to get all site content, but you do need to make a request to the site. You can make a HEAD request to get only the headers. Depending on the site, these headers may contain information about when it was last modified.
Additionally, you can check for a response of 304 Not Modified if you have content cached. This is more often seen with a HEAD request than a GET request, but can be used either way. Like with any request, of course, it depends on how the server decides to respond.
You can look up the standards easily enough, and how you make use of these options depends on what technology you use. But basically a HEAD request is simply asking the server, "Don't send me the page, just send me some basic information about the page." And checking for a 304 response is basically asking the server, "This is when I last accessed this resource, has anything changed?"
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My client redirects to a https://domain.com/Controller/GetInfo?Querystring method. Now my query string is getting dangerously close to the 2K limit, so I need to reproduce this behavior but pack my query string into the content of the messages. Since it would be heresy (etc.) to try a GET with content, I'll use a POST. However, I can't redirect to a POST since a Redirect has no content.
So, what I am looking for is the best MVC 5 pattern to resolve this: I need to provide lots of content, but I want the resulting page hosted on my remote server (i.e. as if I had redirected)
Also, since I use load balanced servers in azure, I'd prefer maintaining my clean stateless server if at all possible (else I'll have to introduce session caching).
#AntP is absolutely right in the comments above. If your query string is approaching 2K, then you're abusing it.
If there's a particular object you're referencing, then you can simply include the id or some other identifying piece of it and use that to look it up again from your data store.
If there's no persistent record of the object, then you can use something like Session or TempData to store it between one request and the next.
Regardless, it's not possible to redirect with a request body, with also means it's not possible to redirect using POST. The reason for this that the a redirect is not something the server does, but rather the client. The server merely suggests that the client go to a different URL. It's then up to the client (web browser) to issue a new request for that URL. Since the client is the one issuing the request, it makes the decision about what data is or isn't included in that request, not the server.
We have existed API like
/api/activiation_code
each time, the activiation_code will be different, then server will create a token for this call and return it, usually each call will have different activiation_code which return different token.
Since this API need server to create something so it is designed as POST.
Can we design this API as HTTP GET ?
What is the pro and cons ?
You could design the API to support GET requests, but I would not recommend this. If your API is accessible via a website, a user could accidentally activate an account multiple times since the URL will be stored in the browser's history. Additionally, web crawlers could potentially supply values to your API through the URL if you support GET requests.
POST requests are much better because the information is included in the body of the request, not the URL. Thus, it is much less likely that something will go wrong accidentally.
Currently i have a wepage where I am sending a ajax request from javascript and in respose for that server is sending a video file which will be by default saved browser download location. I want the user to select download path each and every time for the file download(which can be achieved by changing browser settings which is not suited for me). So i want to include a activex object which can send ajax request and get its response. First I want to know whether is it possible, if yes is there any prototype/examples, or please let me know how it can be achieved.
It is possible; FireBreath has a mechanism called BrowserStreams that would probably work for what you're describing, but honestly I'd suggest against it. See if you can do what you need using an extension; Chrome is dropping support for NPAPI next year and even if they weren't I think it's a really bad idea to use a plugin for something like this.
Up to you, of course. There are examples for making HTTP GET and POST requests in the FBTestPlugin example in FireBreath.
I have been told that a POST in some way does a double send to the server but GET does not. It sounds a bit crazy to me though.
Basically I'm working on a web project where each client calls a web service every 2 seconds from many countries and possible bad internet connections. So we want to make the calls and responses as tiny as possible between JavaScript and ASP.Net.
Security is not a problem and basically the poll is just returning data. Login is required to use it anyway.
I have been told that a POST in some way does a double send to the server but GET dose not. It sounds a bit crazy to me though.
You have been told wrong. The only difference is that POST allows for sending larger amount of data to the server and of course the more data you send the slower it will be. But if you send the same amount of data there won't be any difference in terms of performance between a GET and POST request.
One important thing to note as well is that if you are calling this service from javascript GET requests might be cached by the client browser. So for example if you are calling the same url over and over again using an AJAX GET request you might get cached values and the server never hit. To workaround this issue you could append a random number in the query string which has no meaning for the server but which changes the url and avoids it being cached.
When sending thru ajax post, some developers may have inited post on form submit and a submit button click. Later when they press the send button, both actions get fired. This might be the experience that people who have told you double sending thing experienced.
Note: This double sending of POST is totally a developer's fault. HTTP POST method has nothing to do with it.
is it possible to submit forms with yahoo pipes?
i basically need to log in somewhere, and get some stuff from the members area of a website into a feed.
Although this is not exactly programming related... I guess it is close enough.
No, logging into somewhere is impossible with Yahoo Pipes. Sending the username/password isn't even the only problem here.
The real problem is that most, if not all, web sites that require a log-in depend on a session cookie or something similar. Yahoo pipes can do a GET request, and that's about it. Even if it was possible to send your user name/password in the URL, you would not be able to use the session cookie, so subsequent requests would fail.
So... If you have access to a hosted web site somewhere: Write a small proxy script (in PHP or whatever is available) that does the login and fetches the data. Let Yahoo pipes read from your proxy page. But if you are that far, you can just as well produce RSS format right away. ;-)
I did a pipe that can log in and extract info. is working ok on a simple web form using POST.