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.
Related
I want to know what are the differences between a WPF Browser Application and WPF Desktop Application. I know that the browser application runs on IE and FF, but about the technology, is the same? I mean, we can do exactly the same by the two ways? (Of course, maybe with different UI)
I have this doubt because I'm looking for a book about WPF Browser Applications, but I only see books about WPF (I don't know if is in general or is only for desktop applications :S)
A WPF Browser Application uses exactly the same framework as a WPF desktop application and could run with the same UI, but with restrictions on trust which means that some APIs are not available. There a number of challenges in developing Browser application. A Browser app must be signed with a certificate. Some of the trust restrictions are not enforced at compile time and are only discovered at run time.
In the time since Browser Applications were first introduced, Microsoft developed Silverlight which uses a similar though not identical XAML technology. Silverlight is easier to deploy than a WPF Browser Application and may be appropriate depending upon your requirements.
A Browser Application not only runs in the browser but also with less authority. If you need to read and write local files then go WPF. Browser is good is you want rapid deployment to lots of PCs. Other wise I will take WPF Desktop every time. Most WPF books with have a chapter on XBAP. I like McDonald from Apress.
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.
This question already has answers here:
Why change from WPF to Silverlight 4?
(8 answers)
Closed 3 years ago.
If I understand correctly, Microsoft Silverlight is a lightweight .NET implementation meant to run on the client side, inside a browser. So now I hear about "out of browser" silverlight applications and I'm confused.
What is the advantage of an "out of browser" silverlight application, compared to a traditional .NET desktop application?
An out-of-browser install of a Silverlight application still runs in a security sandbox where as a traditional .NET desktop application won't.
The objective of an OOB is to give the user the ability to lift a web-based application out of its browser container and make it easier to access. Its still a web based application. Its worth bearing in mind that this works on a Mac where as a traditional .NET desktop app won't.
This area has become muddier with SL4 OOB that can now ask the user for elevated trust. Now the sandbox is more relaxed and there are greater opportunities to work with the native OS. However there are still many restrictions in place primarily to support multi-platforms. It would not be desirable if it became a defacto that trusted OOBs tend only to work on Windows. It remains to be seen whether that can be avoided.
So if you're thinking of a full-fledge Windows desktop app then you're probably better off using WPF. On the other hand if you don't need full access to the OS, you can deliver via a web page and/or you want to be able run on both Windows and Macs (and possibly other platforms) then perhaps Silverlight 4 OOB+Elevated Trust may be what you need.
Silverlight 3 out-of-browser apps allow any Silverlight app to have a desktop shortcut, and don't require the browser to be opened to run the app (so technically you could now run the app even if you're offline, since you don't have to fetch the SL app via the web).
With SL 4, you can now have elevated privileges, allowing the SL app to access local resources (such as the network stack and file system).
There's also a simple API call for an out-of-browser SL app to check for updates on startup, and download an update from the server. This could be seen as similar to click-once deployment, but it happens automatically and quickly, so it's more efficient and straightforward than click-once.
Compared to a traditional .NET app (in this case let's compare with WPF, since that's effectively the WinForms replacement), there's very little in the way of installation. No setup program, just the xap file, easily hosted on the web and very quickly installable. SL uses a reduced .NET framework, which might seem like a negative. However, the typical pattern for an SL app is to put most of the heavy-lifting in a service tier. Then, in the service tier you have the full .NET framework and can do pretty much whatever you want (such as accessing databases with ADO.NET).
Libraries are another thing to consider between the two applications. For example, Silverlight 4 natively has built in support for talking to a web-camera and microphone out of the box while WPF and the full .net Framework have a very large third party community of libraries to draw upon which you might need source code for if you wish to rebuild them under Silverlight.
Another factor is limitations in the sandbox, for example, you wouldn't be able to write an application that could connect to any server using any socket in Silverlight 4.
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.
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