Broadcast messages windows server

Instance static property, as you saw earlier in the StockTickerHub class. As you saw earlier, this collection of stocks is returned by StockTickerHub.

GetAllStocks , which is a server method in the Hub class that clients can call. The stocks collection is defined as a ConcurrentDictionary type for thread safety.

As an alternative, you could use a Dictionary object and explicitly lock the dictionary when you make changes to it. For this sample application, it's OK to store application data in memory and to lose the data when the app disposes of the StockTicker instance. In a real application, you would work with a back-end data store like a database. The constructor starts up a Timer object that periodically calls methods that update stock prices on a random basis.

Timer calls UpdateStockPrices , which passes in null in the state parameter. The code checks if another thread is already updating prices, and then it calls TryUpdateStockPrice on each stock in the list.

The TryUpdateStockPrice method decides whether to change the stock price, and how much to change it. If the stock price changes, the app calls BroadcastStockPrice to broadcast the stock price change to all connected clients.

In a real application, the TryUpdateStockPrice method would call a web service to look up the price. In this code, the app uses a random number generator to make changes randomly. Because the price changes originate here in the StockTicker object, it's the object that needs to call an updateStockPrice method on all connected clients. In a Hub class, you have an API for calling client methods, but StockTicker doesn't derive from the Hub class and doesn't have a reference to any Hub object.

To broadcast to connected clients, the StockTicker class has to get the SignalR context instance for the StockTickerHub class and use that to call methods on clients. The code gets a reference to the SignalR context when it creates the singleton class instance, passes that reference to the constructor, and the constructor puts it in the Clients property.

There are two reasons why you want to get the context only once: getting the context is an expensive task, and getting it once makes sure the app preserves the intended order of messages sent to the clients. Getting the Clients property of the context and putting it in the StockTickerClient property lets you write code to call client methods that looks the same as it would in a Hub class.

For instance, to broadcast to all clients you can write Clients. You'll add it later when you write code that runs on the client. You can refer to updateStockPrice here because Clients. All is dynamic, which means the app will evaluate the expression at runtime. When this method call executes, SignalR will send the method name and the parameter value to the client, and if the client has a method named updateStockPrice , the app will call that method and pass the parameter value to it.

All means send to all clients. SignalR gives you other options to specify which clients or groups of clients to send to. For more information, see HubConnectionContext. To do that, add an OWIN startup class:. The HTML creates a table with five columns, a header row, and a data row with a single cell that spans all five columns. The data row shows "loading JavaScript code will remove that row and add in its place rows with stock data retrieved from the server.

The app dynamically generates the SignalR proxies script file. Don't forget to disable dynamic file creation in the MapHubs method call. Update the script references in the code block to correspond to the versions of the script files in the project. In Solution Explorer , right-click StockTicker. If you examine the client code, it will help you learn how the client code interacts with the server code to make the app work. The code gets a reference to the proxy for the StockTickerHub class and puts it in the ticker variable.

The proxy name is the name that was set by the HubName attribute:. After you define all the variables and functions, the last line of code in the file initializes the SignalR connection by calling the SignalR start function. The start function executes asynchronously and returns a jQuery Deferred object. You can call the done function to specify the function to call when the app finishes the asynchronous action. The init function calls the getAllStocks function on the server and uses the information that the server returns to update the stock table.

Notice that, by default, you have to use camelCasing on the client even though the method name is pascal-cased on the server. The camelCasing rule only applies to methods, not objects.

For example, you refer to stock. Symbol and stock. Price , not stock. In the init method, the app creates HTML for a table row for each stock object received from the server by calling formatStock to format properties of the stock object, and then by calling supplant to replace placeholders in the rowTemplate variable with the stock object property values. The resulting HTML is then appended to the stock table.

You call init by passing it in as a callback function that executes after the asynchronous start function finishes. If you called init as a separate JavaScript statement after calling start , the function would fail because it would run immediately without waiting for the start function to finish establishing the connection. In that case, the init function would try to call the getAllStocks function before the app establishes a server connection. When the server changes a stock's price, it calls the updateStockPrice on connected clients.

The app adds the function to the client property of the stockTicker proxy to make it available to calls from the server. The updateStockPrice function formats a stock object received from the server into a table row the same way as in the init function. Instead of appending the row to the table, it finds the stock's current row in the table and replaces that row with the new one. You can test the app to make sure it's working.

You'll see all browser windows display the live stock table with stock prices fluctuating. Suffice to say - the enemy of good is better. Since you were using the task manager, I'm assuming you were doing this on the server itself? If you open a command prompt, type the 'msg' command to get the syntax.

I'm guessing Powershell would be a good way to go for this. The message pops up for me but no one else - yes I'm logged in as an adminitrative user and opening cmd prompt as admin. Upon further testing the message is going through to the users, I'm not sure what the error message is from.

Thanks to all. If you are in a session while doing this, I suspect the problem is sending the message to either your own session, or the 'console', which is I think session 1. It would be curious if you get the same error.

But oh well, it works! To notify users about a server reboot, you can use the -c comment modifier on the shutdown command to send a message to all users that the server is rebooting. Doing this on the domain controller, logged in as domain admin with elevated CMD. Now I get this error: Error getting session names. Doing this on my workstation, from a domain admin account, with elevated CMD. Same error as above, Error My goal is to send a message to all users. For this example, I am sending the message from the domain controller, logged in as a domain admin with elevated CMD.

So my next attempt is to use the file that I define all my users in there, then call the file in the syntax. I cannot find the information on using this file anywhere online, where do I store the file and in what directory? What fields are required in the file and in what format? Perhaps an example file would be useful also as a template. Also please exercise your best judgment when posting in the forums--revealing personal information such as your e-mail address, telephone number, and address is not recommended.

Please note: Do not post advertisements, offensive material, profanity, or personal attacks. Please remember to be considerate of other members. All submitted content is subject to our Terms Of Use. I need to send out an instant message to all users of a domain if i need to restart the server. Share Flag. All Answers. Collapse -. Isn't there a better way. I didn't go away, it's still there, just not used as much, I guess. Broadcast - use net send for the simplest method.

StrataCS is a good way if you have IP phones. Back to Networks Forum.