WPF app to interacts with WCF?

Hello all,

I'm working on a small app for my own use (I'm a musician), this is the scenerio:

1. WPF app that scan a specific folder and list all the files (music sheets, .pdf & .xps docs).

2. Store the file name & location in a SQL CE database.

3. I can use the app to edit the tags (song title, artist, key, additional notes, etc...) and store it together with STEP [2].

4. Changes made to folder (new music sheets (files) got added, renamed files, removed files, etc... are to be reflected in the app if it's running or as soon as it's started.

So I was searching around and found out that I can use the FileSystemWatcher to watch for changes in the folder, and thus can update the database with the changes (insert/update/delete on file created/changed/removed for the file location.) However, if the app is not running, I can't use the FileSystemWatcher to make the changes, so I was thinking to use a Windows Service to keep track and store the changes in the database, and the WPF to points to the same DB and get the file information. So my questions:

1. Should I use a Windows Service (WCF?) to do this job? If yes, what do I need to do to interacts between WPF & WCF?

2. I will be using SQL CE since I don't want the users (my band members) to install additional softwares to run it (SQL Express, etc...) How do I make sure that my Windows Service and the WPF points to the same database that got embeded in the WPF app?

3. Any other suggestions?

Thank you very much. I've been mainly working with asp.net and this is pretty much my first WPF app, so please bare with my questions if they are so obvious Thanks again.

Kenny.

1. A service i.e. Windows Service is unique in that it has no user interface so forget about WPF
2. Yes you need to either create a traditional windows service or use the new (easier) WCF to do this.

vesuvius said:

1. A service i.e. Windows Service is unique in that it has no user interface so forget about WPF
2. Yes you need to either create a traditional windows service or use the new (easier) WCF to do this.

Hi vesuvius,

Thanks for the info... Now how do I make sure that the WCF points to the same database as the WPF app? And I would like both (WCF & WPF) to be installed as 1, so the user don't have to know what is really going on, what should I do?

Thanks again.

vesuvius said:

1. A service i.e. Windows Service is unique in that it has no user interface so forget about WPF
2. Yes you need to either create a traditional windows service or use the new (easier) WCF to do this.

IMHO, WCF is an entirely innapropriate soultion to the OPs problem. WCF is for interprocess/machine communication. All KennyV wants to do is have a background process that monitors a folder or set of folders and updates a database that is shared with an application. That's the kind of thing Windows Services are made for. That's how Windows Search's Indexing Service is implemented.

There's a Visual Studio project template for writing a managed code Windows Service. I believe SQL Server CE is OK with limited local concurrency (just two processes in this case) accessing a single database. Use the registry to store the path to the DB (or DBs) and the settings for which folders to monitor. Perhaps also provide a configuration app for changing settings of the service, as they cannot provide thier own UI.

DCMonkey said:

vesuvius said:

*snip*

IMHO, WCF is an entirely innapropriate soultion to the OPs problem. WCF is for interprocess/machine communication. All KennyV wants to do is have a background process that monitors a folder or set of folders and updates a database that is shared with an application. That's the kind of thing Windows Services are made for. That's how Windows Search's Indexing Service is implemented.

There's a Visual Studio project template for writing a managed code Windows Service. I believe SQL Server CE is OK with limited local concurrency (just two processes in this case) accessing a single database. Use the registry to store the path to the DB (or DBs) and the settings for which folders to monitor. Perhaps also provide a configuration app for changing settings of the service, as they cannot provide thier own UI.

Personally I think it sounds like over-engineering a bit. Why not just have a background thread that starts when you launch the app that re-scans the folder and makes any appropriate changes. Otherwise you're practically reinventing the whole Windows 7 library concept just for one app.

AndyC said:

DCMonkey said:

*snip*

Personally I think it sounds like over-engineering a bit. Why not just have a background thread that starts when you launch the app that re-scans the folder and makes any appropriate changes. Otherwise you're practically reinventing the whole Windows 7 library concept just for one app.

Hi DCMonkey & Andy,

Thanks for the suggestions. I was thinking about rescanning the whole folder each time the app launch, but would it suitable for large number of files (2-3000)?

If I'm going to use this technique, how should I approach it? Something like this:

1. App launch, scan all files in the folder.

2. Compare with the files already in the database (how? will it take too long?)

3. Do insert/update/delete

Step #2 is where I don't know how to approach.

Thanks again for all the suggestions,

Kenny.