I have an application that uses cellphone data connection to communicate with a remote server over web services. However, due to the unreliability of the cell phone network the application doesn't work for as long as the cell network is down. So what I want to do is change the application to process orders directly on the device and upload the orders in the background (like a windows service) when internet is available.
Here's what I'm thinking:
2 Applications
App #1: Change the order taking application to connect to internet at application load to get all settings and save to a sdf DB. Once settings are saved locally the user can process orders and save to database.
App #2: Runs in the background constantly checking db (say every 3-5 mins) for orders and upload to remote server via WCF web service. Additionally after upload is completed updated settings are downloaded back to the device.
App #2 is what I need guidance on. On a desktop I could run a windows service however compact framework of windows mobiles doesn't appear to have a windows service type support.
Any advice?
Why run it as a separate app? In that case you'll have to do cross-process synchronization of data access to make sure that simultaneous access from both processes doesn't cause a problem. Why not create a background "service" thread inside the app itself to do data forwarding to the enterprise?
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I am building a browser based application for document scanning. I have looked at offerings from multiple providers like dynamosoft, asprise, atalasoft etc. My basic question on browser based document scanning is that does any of these products enable scanning from remote machines, using browser based interface? Or should scanner be always connected to the system from where browser is launched?
Yes. Browser based document scanning relies on the communication between a local service and the web client. Usually, you need to download the installer of the local service when browsing an online demo of document scanning at the first time. If you want to scan documents from a remote machine, just deploy the service on that machine. Then change the IP for web socket connection.
For example, here is the architecture of Dynamic Web TWAIN.
The scanner should be always connected to the system from where the local service (not the web browser) is launched.
You can watch the video to see how to use Raspberry Pi as the scanner service to capture documents from iMac.
Yes, There is a Application that enable scanning on remote machine. When someone open the browser a connection between web browser and that local machine application established. This connection is done easily by HTML5 Web Socket. Local application do scan and send this image via this connection to your Browser.
Here is the open source repository,
ScanAppForWeb
I'm hoping this will be helpful, though it's not a direct answer to the question.
After spending a lot of time trying to get WebUSB to work try researching other options, I found a solution that works well for my web app. Simply use scanimage to scan to the server. The client sends and AJAX request, the server builds a command string to run with shell_exec in PHP, then use file_get_contents or whatever with the scanned image. In my situation, there's no reason for the scanner to talk to the client, since the image is going to end up in a database on the server anyway.
See also: https://stackoverflow.com/a/63198443/4509516
Extrieve HTTPTWAIN browser-based document scanning SDK support , document scanning from a remote PC. This require service client to be deployed on the remote PC and Web module should connect to the service using ip and port of the remote pc.
To Know more visit- https://www.extrieve.com/web-document-scanning/
I have a solution which basically contains three components:
• WCF Service that is hosted locally having a back-end SQL Server Express DB and this WCF service is hosted from a Windows Service
• A console application
• A Windows Store Application
This is what they are meant to do:
• WCF service his hosted locally and is used by the console app and the store app for communicating with the database
• The console app adds an image for processing to the database by contacting the WCF service
• The store app will at regular time look for unprocessed images in database via the WCF service and will process them
Now, the difficulty is:
• The WCF service is hosted successfully and is working absolutely fine and I can check that by hitting its URL http://localhost:8081/XYZ
• The console app is also able to submit images to the WCF service and add their local paths to the database
• The store app however always throws the EndpointNotFoundException when accessing the service at that same localhost path
What have I tried:
• I have tried almost everything from searching through stackoverflow to googling and haven't found a solution yet
• I was thinking that it might be a port issue and so I turned off the firewall to check this, but it did not work, and the store app kept throwing the EndpointNotFoundException
What have worked:
• The complete set-up has, however, worked perfectly on my machine. It is strange that its not working on my client's Windows 8 machine.
Point to be noted:
• The complete solution has been developed in Visual Studio 2013 and the App is for Windows 8.1
• I am not sure, but it seems my client has a Windows 8 machine and we are installing the app on that. (Possibly, that might be a problem. But I'll check)
If there is any help someone could provide me, I'll be really greatful. Thanks in advance!
This is expected. Windows Store apps cannot connect back to the local system in production. This loopback prohibition is disabled for debugging.
See How to enable loopback and troubleshoot network isolation
If your app is to be side-loaded rather than deployed through the store then see Using network loopback in side-loaded Windows Store apps
I'm trying to make my store app communication with desktop app through websockets.
I know we can make metro app as a client and do WinRT way of communicating over.
For the desktop server part, i'm planning to write a dll that will contain server code and receive metro texts being sent over.
Can someone please tell if this is possible and how to write server code in a dll and if so should we be using winhttp for wbesockets in server side ?
Windows Store (WInRT) apps are executing in a sandbox which isolates them from network communication with other applications on the local machine (localhost). That being said, this protection can be disabled using CheckNetIsolation.exe. Visual Studio automatically does the same for debugging purposes, allowing you to call e.g. a web service on your local machine during development.
As for the desktop side; to communicate with web sockets client, you can make advantage of WinHTTP. There's a working example on MSDN.
Keep in mind, though, that any application communicating with localhost will not be certified for Windows Store and will require several additional steps to install it:
The Windows Store application package will need to be sideloaded since it won't be published in Windows Store.
Any desktop component it communicates with will need to be installed separately the same way as any other desktop application.
Using CheckNetIsolation.exe loopback exemption will need to be added for the Windows Store app.
If you can avoid it, I definitely suggest you don't try communicating directly with a desktop application from you Windows Store app.
I am making an app for the iPhone in Xcode which needs to be able to send and receive excel data from a windows based machine. Making the app is no trouble but what would I need from a PC to access the app data?
Firstly, I wouldn't be using Excel as a data storage program. What you really should be using is a database hosted on a web server with a PHP interface etc. If you choose to go the database route, then you can easily use a Windows machine.
Though if you choose to stick with Excel, it would be theoretically be possible given that people have made apps to have full control of a computer remotely via an app. I just think that this approach is going to be very hard to set up, and will be a lot more clunky than any sort of web server set up. Don't forget that you can get free web server services if the data level is low.
As you mentioned, this PC won't have access to the internet. Assuming you aren't willing to fix that, I guess you'd be left with a Bluetooth or local wifi option. Having to plug it in would really defeat the purpose of an app, and I don't think that iPhones can even do that without mad hacks.
An alternative idea is to build an app that links in with some free web server service, then build VBA code to download it to your Excel sheet. When you plug your iPhone into your PC, use the hotspot to get internet access.
I have a traditional Win32 program which gets some data using WMI (and it cannot be fetched using API available to Metro apps). Now I want to make a tile with part of this information. As I've understood, it's impossible to simply send this data from Win32 program to the Metro application. What's the preferred way to do such thing?
There is no direct app to app communication method. What you want to do can be accomplished in several ways, however. Your Win32 app could write data to a location on the file system that a Metro style has access to. Also, you could synchronize your Win32 app with your Metro style app using the cloud. You need to be careful, however, as this might violate some of the app certification requirements.
If you are simply writing something for yourself (not concerned with publish your app), you might consider taking the functionality that currently have within your desktop app and encapsulating it within a wcf service running on localhost. Metro apps can call wcf services.
One option would be to have your Win32 program create the tile XML and deposit in Windows Azure storage (or really anything accessible via a URI) and then your Windows 8 Store application could subscribe to that tile via a Periodic Notification.
There are some constraints here which may or may not be relevant to your application - like the refresh rate of the tile (discrete periods from 30 minutes to 1 day) and the machine must be connected to the network when the poll from the URL is made.
You might be able to incorporate a background task to do something similar.