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How to refresh aspx page from sql server

How to refresh aspx page from sql server.I am using asp.net,C-Sharp with SQL Server 2008.What i mean is i have table, say Table1.If any DML operation is performed (Update,Insert etc) to Table1,then my page,say Page1.aspx should autmatically get refreshed.I can't use timer for refreshing the page.I need to trigger the refresh from database.

Even though the server may be notified when data has changed, the real challenge is communicating those changes to the client in real-time without requiring a timer or user interaction.
You have a couple of options:
Your best bet is to use a WebSocket, which enables bidirectional communication between the client and server. This is the solution I would pick.
Here are some examples using WebSockets:
Building real-time web apps with WebSockets using IIS, ASP.NET and WCF
HTML5 C# WebSockets Server and ASP.NET Client Implementation
C# WebSocket Server
WebSockets in ASP.NET 4.5
WebHooks and WebSockets in ASP.NET
There are a few good libraries around too that will take care of most of the leg work. A couple to check out are WebSync and PokeIn. Both products offer decent documentation and community editions that you can download for free.
Here are some tutorials to check out:
WebSync Tutorials
PokeIn Basic Tutorial / PokeIn Advanced Tutorial
Use AJAX to poll for changes every X number of seconds. If changes are detected reload the page, otherwise do nothing.

You probably want to look into the SqlDependency object. This object will notify you of changes to a specified database query in real time. When your application receives a message from the database, you can simply refresh the page in your code-behind.

I wonder if you could adapt SignalR to send a message to the client to prompt a refresh?
This tutorial could get you started.

Push content to client after page is loaded

I wonder if the following is possible:
I have a dll that I have referenced in my web site. This dll makes a remote socket connection. The socket connection is waiting in the background and the dll reports back data through events after the socket has received some data.
The connection is opened during load of page.
Now, I would, for example, like to update a label on the page when new data has arrived.
I am not sure how this would work. I assume that I could set some kind of timer on page that updates a control but it does not seem "optimal" as I already call code behind through my events. "Optimally" the UpdatePanel or whatever updates the interface would wait for events and "update" when events has occurred and not based on time.
My question is - is this possible?

You can use techniques called "long pulling" or "web sockets".
There are libraries, like SignalR that can help you.
They generally use web sockets when client's browser supports and long pulling when not.
Using these libraries you can "push" commands/data from server to client's browser, just as you want.

Server cannot push the client, this is the rule how web works.
There are two possible ways to complete your task.
Put timer on the page and make requests on server too see, if something changed
Open long pulling connection between client and server, like facebook does. That listens
to the events and gets data from the server. It can be, for example xmpp or any other.

You should think about turning this around; rather than initiate the call from the code behind asynchronously and then update the client, you should deliver your original page to the client.
Once the page has been loaded client side, you can make an AJAX call to the server to retrieve the data you want - and display a little "I'm loading" symbol while this happens.
Page Methods are ideal for this.
The classic ASP.Net web page is supposed to last for the duration of the users request. When a postback happens, it effectively rebuilds the state of the call from the user's viewstate, session and any other state you've maintained. It never cares if the user goes away, for example (although it might feel a bit lonely).
Having it hang around for longer is problematic in a number of ways, however, you can implement client callbacks. However, although the server initiates this, the client manages the lifecycle, so it's analogous to page methods.

How do I implement WebSockets from scratch with the .NET 4 Framework (and nothing else)?

Ok I want to build a simple chat app where people can go a url, type in a name and a message and click submit and it will basically show that message to everyone that is current connected.
Firstly i would like to state i've had zero experience in sockets programming and the like. I'm simply a web 2.0 person building websites with css/html/js/ajax and backend i have asp.net on vb and sql server for database.
The many tutorials i've read linked me to http://superwebsocket.codeplex.com/
I've downloaded it, but im totally lost. i can't get the samples working and i don't even know what to run.
So basically coming from an ajax background, i was wondering why do we even need to download any additional stuff to do web sockets? I mean in ajax i can simply create a asd.aspx file and use Response.Write(text) (text based on the input which are available through dissecting the url) and voila, the server side is done, all that's left is just to create new XMLHttpRequest and stuff in the client side.
So ok I'm not worried about the client side part of Web Sockets. but the server side part of web sockets is just difficult. so in the client side i have this: ws://localhost:8080/websocket. Is it true that it will work if is also an .aspx file as such: ws://localhost:8080/websocket.aspx ?
I'm wondering so how do i continue from here? in Ajax i will supply parameters from client in the url as such: page.aspx?a=1&b=2 and do output in the server using Response.Write it's all clear but how do we do it in web sockets?
I mean of course i do not demand a full explanation with a forum reply but if someone could link me to a tutorial/book that actually does explain these stuff it would be great.

Microsoft's implementation has a full chat client sample for both HTML5 and pure C#.
http://html5labs.interoperabilitybridges.com/prototypes/websockets/websockets/download
I'm guessing this implementation is what would end up in ASP.NET and .NET framework so I'm using it because of that.

Queueing framework solution

I would like to address such a issue: I have a HTML form (like register form) which submission sends email. Now I send it as a part of page request. Obvious drawbacks:
makes request longer
sometimes smtp server is down, or timeouts and emails are not sent
When working with PHP I used a solution that based on queue - I had been putting an object/xml to queue host, and then some kind of client checked that queue. If queue task was sucessfully handled it removed task from queue. I wonder, is there a similar implementation on Windows / .NET platform ?
Thanks,Paweł

There is robust queuing offered by MSMQ which is easy to use in .NET. Accessing Message Queues might be a good place to start.

AH - why?
I have a HTML form (like register form) which submission sends email.
Have the submission write the email to a local drop directory, then use the SMTP service of the Windows system to submit them to your providers email server. Alternatively use your own service to copy them to the outgoing email pickup folder (I do that so I can put in a code pointing to the website for tracking).
These are provided standard methods.

You don't neccessarily need a queue as such. You can use the SendAsync method on the System.Net.Mail.SmtpClient class. That will return immediately and not block the page.
See: http://msdn.microsoft.com/en-us/library/x5x13z6h.aspx

Website but more like chat application behaviour

Hi I wanna make a website preferably using asp.net 3.5 in c#. In this web app, I need to push messages very frequently. (like if sender sends a message, it should immediately reflect to the receivers). So more like chat application but not bidirectional.
My question is how can i refresh receivers webpage immediately?
or How can i push message to the receivers immediately?
any help is highly appreciated?

I'm guessing you're talking about features like Facebook Chat. According to various facebook dev blog posts, I believe they use ajax to make a long polled request; meaning as soon as one user sends a message, theres another ajax request made which isn't responded to by the server until there's something to report (i.e. a new message). This is often called "Comet".
Note: do NOT attempt to do this on a standard server setup - most server software starts a new thread for each request. You'll need custom server software to avoid this. Unfortunately, I've searched for hours in the past and can't find a definitive answer to which software accomplishes this best.

You might consider using a Comet Look at the "implementation" section for some ideas.