I have an app I'd like to run in the browser but do not want to deal with the fairly primitive development environment that the browser is. I have a few high level questions about Silverlight 3 (I've never used it):
1) What environments/browsers support Silverlight 3?
2) Would my users (who would be world-wide) have to install Silverlight 3 on their computer before they could run my app? I assume so. If so, is this a major undertaking?
3) Would my app be permitted to save files to the user's computer, and read them back?
4) Is Silverlight 3 fairly mature? IOW, would this be a frustrating development experience or are the tools/functionality far enough along where they allow the developer to do mostly what he/she wants to do?
Thanks. That should get me started.
Silverlight is supported on Windows and Mac OS X, in IE, Firefox and Safari. There is a port to Linux, Moonlight, which is developed externally from Microsoft but with their collaboration.
Yes, your users would have to install Silverlight 3. This is reasonably simple and the Silverlight project wizards generate code that will prompt the user to do so. The overhead is similar to installing Flash. Permissions may be an issue for corporate users though: many companies have policies that do not allow users to install arbitrary plug-ins, and the admins may not have made an exception for Silverlight.
Your app would be permitted to save files to isolated storage (with a size limit), or if you prompted the user to select a save location. Your app would not be permitted to save files to arbitrary locations without informing the user and allowing them to change the path. Isolated storage is private to your app and could not be used to read other apps' data or share data with other apps.
Silverlight 3 is a fairly mature runtime, but the development tools are not as mature as the rest of the .NET toolchain. In particular diagnosing and debugging XAML exceptions can be very frustrating (Silverlight tends to throw AG_E_UNKNOWN_ERROR or HRESULT_E_FAIL with little, no or misleading diagnostic info rather than a WPF-style XamlParseException). That said, it is still C# and a variant of the .NET Framework, so you get all the Visual Studio goodies like Intellisense, a nice visual debugger, etc.
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Looking for opinions. I'm working on a mid-sized 3-tier ASP.NET project (.NET 2.0 and Visual Studio 2005) with an Oracle on Unix back-end, some beefy MS web servers, and IE browser clients. Performance is pretty bad, and users feel the UI looks outdated as well. We may have an opportunity soon to redesign and rewrite the entire application from the ground up, and I'm wondering what the current or recommended MS platform is.
I was involved with WPF and Silverlight on a different contract when MS downgraded support for Silverlight in favor of "HTML5" for Windows 8 and Windows Phone a few years back. I'm not trying to start a flame war between how long Silverlight or even WPF will be around, but I'm looking for some modern alternatives as of today, April 2013. The one requirement we can't get around is that we can't install something on each and every user PC throughout the client organization.
My own background is in WinForms and C# more so than any of the above, but everywhere I turn it seems developing any new LOB apps in WinForms isn't done much anymore.
Whatever happened to the Application Server platform and apps run thru Remote Desktop? Does it still make sense to develop desktop apps and deploy to app servers and just put a shortcut on each user's desktop, or even map a drive letter like we used to do back in the day?
Your $0.02 would be appreciated!
I would definitely consider doing it as an internal web site.
The UI would be HTML5 using the "single page application" (SPA) for each function you need. Each function would be on a page that is loaded when the user needs it. The javascript/ajax code in the browser would interact with the web server which feeds back the raw data needed to be displayed.
Using Active Directory, you can have full security and customization per person.
If you need lots of interactivity, then you'd also want to consider including SignalR in the mix. (That is one of the "new" MS tools!)
If you can't install anything in the end users' PCs then go ASP.Net. Anything else will require installation.
You can make a web application more appealing to the users by having a good designer and a LOT of javascript. Not remotely comparable to the power and beauty of WPF, but that's your best bet.
WPF is part of the .Net framework and will not run without it installed.
Silverlight could also be an option, but it still requires an installation (although minimal, 4 MB, less-than-2 minute install), but an install anyways.
WinRT only works in Windows 8. It's not supported in lower versions (Vista, XP, 7). So I don't think it's an option as of now (unless all your users have Windows 8, of course).
And no, winforms is not an option. It's also part of the .Net framework, and even if you could get it installed, it doesn't make any sense having to deal with the limitations of it, having many much much better technologies at your disposal.
I am thinking of making a website using a WPF browser application, but would like to know the minimum requirement a client/internet user must have to access this website made by using WPF.
Please state even the very basic requirements, like does he need to run Windows or will even Mac and Linux do, with any browser to view the application?
Three main requirements:
User has to run the application under Windows;
The browser should be either Interned Explorer or Firefox;
The .Net Framework should be installed on user's machine.
One requirement is to have the .NET framework installed (same version as you used to build your application), so that means it will only run under Windows.
Also I think only Internet Explorer and Firefox support XBAP applications.
Also I assume that you know there is a lot of restrictions for you, the developer, on what is allowed or not compared to a full trust program. For example, the file system and registry among other things are restricted in a WPF browser application.
I have been using WPF for a while, and I keep on realizing again and again that Microsoft invests its efforst in Silverlight, not in WPF (RIA Services, default theme, controls and more).
I thought it might be a good idea to migrate to Silverlight (i.e. creating standalone desktop apps with Silverlight 4.0), the question is whether this is possible or not.
BTW, I think LightSwitch applications are generated with Silverlight as standalone desktop apps.
From MSDN:
Silverlight 3 applications are no longer restricted to running in a browser. They can be run in a browser or it they can be detached from the browser and run from the desktop. These out-of-browser applications allow you to bring the richness of Silverlight 3 applications directly to the desktop without the restriction of running within a browser.
Link: Building An Out-of-Browser Client With Silverlight 3
It is possible to create standalone desktop apps(Out of browser apps) with silverlight version 3.0 or higher and it works great. Now it is also possible to install the out of browser app even without opening a browser as shown at this blog post .Silverlight is awesome and silverlight apps even run on MACs and Linux(limited support)
However, it is not true that Microsoft is only investing in silverlight. Microsoft is investing in WPF too. Though it is possible to create out of browser applications with silverlight, they have lot of limitations when compared to a full blown WPF applications.Dont forget that silverlight is just a subset of WPF, for example, silverlight doesnt have ADO.NET, Hardware device access etc. So if your application is merely a business application and you dont have to access hardware devices or database directly then silverlight might be an option, however if your application accessing client machines hardware resources directly then you are better off with WPF.
My suggestion is, If you know before hand that it is going to be a desktop application then go with WPF(or may be even XBAP). In my experience, useful applications grow with time, new features are always requested time to time. If in future,a feature is requested that cannot be accomplished with silverlight and can only be accomplished with WPF, then you will be in a big trouble because you need to rewrite your app in WPF and it will be hard for you to convince your CFO to allocate more fund just to implement one feature. Silverlight is not designed to develop desktop applications, its main goal is multi-platform support.
Silverlight 3 supports Out-of-Browser functionality.
Quote from Wikipedia silverlight page :
Silverlight 3 supports Out-of-Browser experiences, i.e., Silverlight applications can be installed to the system for offline access (provided the application manifest is designed to allow local installation) where they run outside the browser.
Also here is a quick howto
Out of browser applications have the same security restrictions as in browser applications.
With Silverlight 4 you can create full trust applications which have full access to the computer.
More on Network Security Access Restrictions in Silverlight
If you mean Out of Browser apps, certainly. The Seesmic Desktop 2 app is an excellent example of one of these apps, with it's own updating mechanism. Seems a no brainer to use the XAP/MEF plug-in Model and Silverlight in this manner.
Seesmic Desktop 2
We're developing an OOB app along the same lines, one internet download and you're done. You're not going to get exactly the same APIs as you get in WPF, though.
As others have pointed out, Silverlight apps can be installed to run 'out-of-browser', but even with elevated trust they still have significant restrictions on what they can do and certainly don't have "full access to the computer".
Creating an app from scratch, you may want to consider parallel Silverlight & WPF builds. The code can more-or-less be shared by adding the .cs files from one project (e.g. WPF) to the other (Silverlight) using "Add As Link". The XAML files cannot be linked this way and need to be duplicated, but that may not involve much more than copying & pasting, depending on your structure. There're good examples of this on the web.
Developing both types in parallel would likely involve a lot less effort than having to abruptly switch types at some point and discovering incompatibilities/limitations too late.
Silverlight Out of Browser technology and WPF ClickOnce on the surface have similarities. Easy and simple deployment, the ability to specify the level of trust access to the underlying host, etc.
What are the key issues I need to consider when choosing one over the other?
To put a finer point on it, I'll be deploying LOB apps on a corporate network running only windows computers.
The big one is cross platform compatibility. If you need you app to run on a mac as well as windows (not sure if Silverlight is supported in Linux yet) then use Silverligt. If you want to make an assumption that all your users will be in a windows machine then go WPF.
Obviously WPF has a much richer toolkit than silverlight so it may well be that silverlight just isn't an option. If I was just building for windows though I know my job would be easier in WPF.
Given that you are targetting a private infrastructure running Windows, two points worth thinking about
Wpf has a richer control tree, whereas Silverlight is a reduced set for compact size
Wpf requires .Net framework installed locally, whereas Silverlight has its own platform independent browser-based runtime
While your target platform will likely have the latest .Net framework installed, rendering this last point moot, keep in mind any updates to the framework [ie .Net4.0 and any future updates] may require a restart of the machine - which is a major pain point for businesses that demand constant-on stateful desktops [ie anything in finance, like banks and trading].
As with all problems, your requirements, not the technology, should inform your solution. :)
You mentioned trust access to the host which I think rules out Silverlight unless you want to run SL4 (beta).
We recently went through a lot of discussion about file system access. Silverlight 3 runs in a partial trust sandbox more or less. You can't maintain a pointer to files in the files system outside of your application's isolated storage. This was an issue for us as we wanted the user to be able to use the application to reference odds and ends on your file system. That said you can allow the users to load and save files from anywhere on the system but you just get/or push the file stream and (to the best of my knowledge) don't have access to the folder or file path information.
Silverlight 4 (in beta) has support for your application running in full trust mode. I haven't played with this yet however and can't speak to how well it works.
In talking with a lot of people who work with both Silverlight and WPF, even those who are excited about Silverlight and push for it strongly, I hear a lot of the say fairly emphatically that if you are going to be developing exclusively for a full-trust Windows environment, WPF is hands-down the obvious choice.
That's not to say that Silverlight is an inferior product or that there aren't times will Silverlight will be the clear winner. But when you say "I'll be deploying LOB apps on a corporate network running only windows computers," it sounds like WPF is the clear winnder.
You could decide to go down the Silverlight route in anticipation of all of the great new OOB feature os SL4. I've even heard rumors that SL and WPF will eventually merge, so it may not even really matter, right? Well, I think what you'll find if you go with Silverlight is that some of the advanced features that you thought were there weren't there in the way you expected. For example, SL4 will be able to run in "Elevated Trust" (not full trust) and you might find this limiting at a frustrating point in the project where a lot of your code base is already in Silverlight.
Certainly keep your eyes on Silverlight, but for your current business case, WPF will likely be the best fit.
We are planning to build a new integration component that can provide us access to user's machine installed apps from our web site.
The first word that came to me was ActiveX, but our expertise with the technology was not the best in the past.
Thinkink a lit bit more, the work Silverlight also came to my head, but the full trust thing was one of the few things I remembered reading about the technology..
The question is: is there a way that Silverlight (2, 3, 4, whatever) can run as a full trusted application from within the browser?
Links are appreciated.
Filipe
Unfortunately, no. Full trust is a feature of Silverlight 4, currently in beta, and is restricted to out-of-browser applications.
Additionally, full trust SL4 applications do not have unrestricted access to the system (particularly file system), though this may change before before release (if I have anything to do with it).
Edit: If you are considering ActiveX (which is Windows/IE only), you might want to have a look at WPF, since it can run full trust from the browser (if it's in a trusted zone).
No, like Richard said, this is not at all possible inside the browser, even in SL4. There is a sandbox, and you live in it. You can talk to web services, other Silverlight applications or the browser.
By talking to the browser, I mean you can talk to the DOM and the Javascript engine. We needed to launch a Windows application and communicate to it via Silverlight. We accomplished this by putting a small ActiveX control in the web page. It is responsible for launching the WinForms application and handling inter-process communication to it.
This method has many drawbacks: It can only work in IE, and it only works in Windows. You might also run into permissions issues. The ActiveX component needs to be installed along with the desktop application, or as an additional download. The deployment story there is pretty awful, if you ask me.
In our case, the analysts were willing to deal with the restrictions for the re-usability of an existing application, and we consider it to be an optional feature.
Does it have to be a web application? sounds like you want a desktop app. It can be easiliy distributed with one Click deployment. Will work on windows only but since you were considering ActiveX sounds like that's what you need.
Well - if you're hosting the silverlight control from an ASP.NET application - Believe you have access to
Request.ServerVariables["AUTH_USER"];
...and you can pass that on to your control as a parameter.
D