Re: WCF How to specify max and min value for a data member? - WPF Discussion Boards

6-Jul-09 1:52

Karl's exactly right. You wouldn't apply the rules on the data member because this is just a contract - it's not a business rule, because your rules may change, but your contract should remain the same. I would also add a check in your client code as well.

"WPF has many lovers. It's a veritable porn star!" - Josh Smith

As Braveheart once said, "You can take our freedom but you'll never take our Hobnobs!" - Martin Hughes.

Re: WCF How to specify max and min value for a data member?

cateyes996-Jul-09 16:00

cateyes99

6-Jul-09 16:00

I think it's still useful if it's able to specify some constraints on data contracts, the reasons are the same as it in XSD. Besides, when publish those data contracts, WCF still makes use of XSD, right?

Re: WCF How to specify max and min value for a data member?

BrowniePoints6-Jul-09 5:12

BrowniePoints

6-Jul-09 5:12

As of right now there is no native Attribute-based method of doing this. However, it is not difficult to create your own framework and set of attributes to encapsulate this behavior.

Soon (well more like next year), Microsoft will be releasing the RIA services framework for Silverlight. It includes an attribute based method of providing validation. Eventually, it will be made available for WPF.

If you have a more pressing need, this is something I've been looking into and could be convinced to accelerate my process on it. I've been a bit stagnant lately and need to get my finger on the keys (outside of work). Let's connect and I can get information on what you would need a validation framework to do and how you'd like to use it.

Re: WCF How to specify max and min value for a data member?

cateyes996-Jul-09 16:53

cateyes99

6-Jul-09 16:53

That's be great, thanks very much.
My email

Does MediaPlayer support AAC format sound files?

fjparisIII5-Jul-09 13:40

5-Jul-09 13:40

Does anyone know the answer to this question? I can' find the answer anywhere. I found this information at this[^] site:

"Because of its exceptional performance and quality, Advanced Audio Coding (AAC) is at the core of the MPEG-4, 3GPP and 3GPP2 specifications and is the audio codec of choice for Internet, wireless and digital broadcast arenas. AAC provides audio encoding that compresses much more efficiently than older formats, such as MP3, yet delivers quality rivaling that of uncompressed CD audio."

Therefore it would be most surprising if MediaPlayer doesn't support this format. What are the file extensions for AAC? I haven't been able to find out that information, either.

Re: Does MediaPlayer support AAC format sound files? [modified]

Christian Graus5-Jul-09 14:16

Christian Graus

5-Jul-09 14:16

No, I am sure it does not. Why would it be surprising ? The media control in WPF barely works, why would it have all the latest formats in it ?

Christian Graus

Driven to the arms of OSX by Vista.

"! i don't exactly like or do programming and it only gives me a headache." - spotted in VB forums.

I can do things with my brain that I can't even google. I can flex the front part of my brain instantly anytime I want. It can be exhausting and it even causes me vision problems for some reason. - CaptainSeeSharp

fjparisIII5-Jul-09 14:59

Re: Does MediaPlayer support AAC format sound files?

5-Jul-09 14:59

I'm absolutely shocked to hear this. If what you say is true, I was completely mislead by Matthew MacDonald's book, Pro WPF in C# 2008 and had big plans for adding music to my application, which has been requested for years.

Christian Graus wrote:
Why would it be surprising ?

Because MacDonald's book makes statements like this: "The support WPF provides for audio is a signficant step up from previous versions of .NET...WPF gives you the ability to play a wide variety of sound formats, including MP3 and anything else supported by Windows Media Player."

You also say,

Christian Graus wrote:
The media control in WPF barely works, why would it have all the latest formats in it ?

According to this [^] article, AAC has been around for ten years. I'd hardly call that one of the "latest" formats. And who said it had "all the latest formats" to begin with? I asked about one format. Are you absolutely certain you know what you're talking about? Sounds as if you got up on the wrong side of the bed this morning, and I need to do some more research to find out whether it's even worthwhile for me to embark on this project.

[Edit] So here is a quote from another book, Windows Presentation Foundation Unleashed: "You won't be able to build a professional audio application solely using WPF, but you can easily enhance an application with music and sound effects!"

"Easily enhance" sounds a long way from your, "media control in WPF barely works" assertion. I just want my customers to be able to start some sound files when they start a picture show. If they have AAC files and I can only support MP3 files and they absolutely have to play their AAC files, I also found out that there are readily available conversion tools that will go from AAC files to MP3 files, so I don't think your alarmist attitude about "media control in WPF" is warranted for the simple things I want to do. So go sow your sour grapes somewhere else, and next time try to be a little more constructive.

modified on Monday, July 6, 2009 9:43 AM

Christian Graus6-Jul-09 9:43

Christian Graus

6-Jul-09 9:43

fjparisIII wrote:
Because MacDonald's book makes statements like this: "The support WPF provides for audio is a signficant step up from previous versions of .NET...WPF gives you the ability to play a wide variety of sound formats, including MP3 and anything else supported by Windows Media Player."

ROTFL. I can play all that in ANY C# application. And, that's exactly what I thought I said. IF I didn't, I must have deleted it, bc I typed it in at first. It uses WMP, so it plays what WMP plays, which probably means you can play other formats IF you install a filter for WMP support.

They've added NOTHING, they gave you WMP, same as Winforms.

fjparisIII wrote:
. Are you absolutely certain you know what you're talking about?

Yes. I have written a great many applications that use sound and video in C#, in and out of WPF. I was making a generalisation.

fjparisIII wrote:
, I also found out that there are readily available conversion tools that will go from AAC files to MP3 files

I'd have assumed you knew that already, sorry. You should have asked.

fjparisIII wrote:
so I don't think your alarmist attitude about "media control in WPF" is warranted for the simple things I want to do.

I was talking in general, about my general experiences with it.

fjparisIII wrote:
So go sow your sour grapes somewhere else, and next time try to be a little more constructive.

http://thingsihateaboutmicrosoft.blogspot.com/[^]

I am doing both of those things. Where Microsoft frameworks have bugs, I am not scared to say so, and I have a blog to tell people how to work around them.

fjparisIII15-Jul-09 8:52

15-Jul-09 8:52

Christian Graus wrote:
Why would it be surprising?

It might be surprising because MP4 has been around for a decade and WPF has only been around for about 3 years. But in looking around, I didn't find a free MP4 codec, so maybe MP4 isn't in the public domain yet and that's why Microsoft doesn't offer it for free.

Christian Graus wrote:
The media control in WPF barely works

What do you mean by "barely works"? I got MediaPlayer to work perfectly the first time I tried it with a list of MP3 files I fed into it. All of the properties like Volume, Balance, and SpeedRatio work as advertised, and you can start, pause, and stop music files, and cycle through a list of music files with the same MediaPlayer instance, all without a hiccup.

If all these things work, then how can you say it "barely works"? When I read "barely works" from your answer, I expected intermittent and distorted sound, or even crashes, and approached my development effort with trepidation. I'm greatly relieved to report that none of that happens. The music sounds wonderful and the MP3 sound files play flawlessly. I'd say the MediaPlayer class works great and exactly as advertised, and that your answer is greatly misleading, unless you were using the expression, "barely works," in a sense with which I am completely unfamiliar.

Christian Graus wrote:
why would [WPF] have all the latest formats in it?

How many of the "latest formats" have come out since WPF was introduced? I don't know of any, but I'm new to this sound game. In any case, I wasn't referring to "all the latest formats." I was referring to the AAC format, which is just MP4. As I'm sure you know, that format has been around for 10 years.

Pete O'Hanlon5-Jul-09 23:12

5-Jul-09 23:12

AAC is supported in MP4, F4V and some MOV files. Whether or not you'll be able to play them properly depends, to a large extent, on whether or not you have the right Codecs installed.

"WPF has many lovers. It's a veritable porn star!" - Josh Smith

As Braveheart once said, "You can take our freedom but you'll never take our Hobnobs!" - Martin Hughes.

fjparisIII6-Jul-09 3:42

6-Jul-09 3:42

Pete O'Hanlon wrote:
Whether or not you'll be able to play them properly depends, to a large extent, on whether or not you have the right Codecs installed.

I know nothing about music files and codecs and want to support music only as a "nice touch" to my main application which is to display large collections of photographs in dozens of different levels of refinement. So I'm restricting myself to the MediaPlayer as I don't want to get into anything low level for functionality as peripheral as this. I want to start the music when photos start showing, playing one music file after another until the user stops showing his photographs.

I should have phrased my question, "does MediaPlayer support AAC?" and I guess the answer is no. But I have found out that there are lots of free utilities that convert AAC to MP3 and so this is not a critical issue. If my application was primarily for playing music I probably wouldn't even try it in WPF. Apparently it would actually be simpler for me to go back to MFC, COM, and Win32. But for my simple audio needs, WPF is the quickest way to get there, especially since I've already got 75,000 lines of code invested in my photo showing application.

Pete O'Hanlon6-Jul-09 3:59

6-Jul-09 3:59

fjparisIII wrote:
"does MediaPlayer support AAC?" and I guess the answer is no.

The answer is yes - but you need a codec installing. The answer to "does MediaPlayer support AAC out of the box?" is no.

"WPF has many lovers. It's a veritable porn star!" - Josh Smith

As Braveheart once said, "You can take our freedom but you'll never take our Hobnobs!" - Martin Hughes.

fjparisIII6-Jul-09 4:28

6-Jul-09 4:28

Pete O'Hanlon wrote:
fjparisIII wrote:
"does MediaPlayer support AAC?" and I guess the answer is no.

The answer is yes - but you need a codec installing. The answer to "does MediaPlayer support AAC out of the box?" is no.

What is involved in "installing a codec"? Is this something the user can do after they buy my application, or is it something I have to build into my application?

Pete O'Hanlon6-Jul-09 4:33

6-Jul-09 4:33

The user can do this after they buy your application, but you may want to offer some default codecs in your installer, bearing in mind that some codecs work well in x64 and some don't. Some of your users will probably have favourite codecs installed already, so it's always a good idea to let them bypass the installation phase.

This KB[^] describes the process of installing and removing codecs.

"WPF has many lovers. It's a veritable porn star!" - Josh Smith

As Braveheart once said, "You can take our freedom but you'll never take our Hobnobs!" - Martin Hughes.

fjparisIII6-Jul-09 6:13

6-Jul-09 6:13

I don't think I want to get involved in installing codecs. If my application was focused on sound that would be a different matter.

If the user has pre-installed sound codecs, does this mean that if a user has installed a codec for AAC files that MediaPlayer will run AAC files automatically? What are the file extensions for AAC files? I haven't been able to find out this information.

BrowniePoints6-Jul-09 6:54

BrowniePoints

6-Jul-09 6:54

AAC is an Apple Codec I believe (used in iTunes and QuickTime). Is there a reason you're so adamant about AAC? Do you have a ton of these laying around? I'd say you're better off using MP3 or WMA for audio if possible.