I need some advice on a method to produce real-time or close to real-time data refreshing in my VB6 application. The application has a visual display using MSHFlexGrid of inventory available for theater seats. A number of order entry clerks can be accessing the data at the same time.
How can I refresh the data display when changes are made, so that the clerks see real information and don't run into conflicts? Ideally, I'd want each client workstation to send a message to other workstations when the data updated. But what's realistic in VB?
I've thought about a few different methods, but none seem that attractive. And I don't want to go down a deadend. What do you think is the best way to acheive this?
Some of my thoughts:
1. A DCOM/ActiveX thing that acts asynchronously (would require enormous learning on my end)
2. Upgrade to VB.NET and use tools that it has?
3. Set a timer to refresh the page. But what cost in processing power, etc?
4. Find a control that will work with little modification
5. something simple that I haven't thought of yet ...
How about a winsock control and UDP protocol. Each time a seat state is changed the station that is affected broadcast message, all others are updated.
Thanks ... going through the Winsock stuff now, that looks like a reasonable way to do it (and much easier than my other ideas) ... will probably have some questions once I start
There is an API which triggers an event when a change is made to a given directory.
In your case, all that needs happen is that when a Seat is allocated this will cause a change in the Seating Database which will trigger the change event in the Watch Directory program, which will then trigger you to refresh the Grid.
Have a look at the attached file - it works so well!
Thanks George. How could I do that for just one table (in SQL Server)? Is there another API for that or would I have to put it in a different directory, or?
Thanks for the input -- sorry to be so newbie-ish, but I'm stretching myself to learn this all quickly. [I've finally given up programming in Paradox and dBase ]
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