I am new to silverlight. I have been trying to patch up a silverlight app that makes a get request to some site over the net, say google. However, I keep getting the system.security exception again nd again. I read various other posts and what i gathered is that for these things to work u need to choose HOST APPLICATION IN A NEW WEBSITE option while creation of the project, i have done that, but still get the same exception. I downloaded the app from http://www.shinedraw.com/data-handling/flash-vs-silverlight-simple-http-post-request/ and ran it by clicking debug in VS2010, still it gave the same exception.
Please tell me what i am doing wrong, i know its cross domain issues, but dont know what else to do.
The second answer at this post - WebClient.DownloadStringAsync throwing Security Exception in Silverlight, I think, offers a workaround, but does this means there is no way to access such services from silverlight directly?? -
Experienced users please explain.
You cannot call a web service other than from your own domain directly from a Silverlight application. If you want to to this, you would have to install a cross-domain policy on the server that hosts the service. But you can always install a web service within your own web application (that hosts the Sivlerlight app) and call the other service from that service. It's one sercie call more but it works also with services you don't own.
Related
Last year someone reported encountering this problem ("The Silverlight project you are about to debug uses web services. Calls to the web service will fail unless the silverlight project is hosted in and launched from the same web project that contains the web services.") and accepted the answer to "set the web project which hosts the Silverlight application to be your startup project."
I'm seeing the same message, but think the solution might have to be different. I am building in VS 2010 a Silverlight application to access the Google Weather API, with VB as the code-behind. The API will return a XML file with data for the specified city (ex., "http://www.google.com/ig/api?weather=london,england"). The Solution Explorer only shows my VB/Silverlight project ("GetWeather"), and the Project Properties dialog box shows the Startup Object as "GetWeather.App" -- the only choice. I'm trying to use a WebClient object to make the call and an XDocument object to parse the return. But I repeatedly get the above error message, with no other result. What am I doing wrong?
Thank you in advance!
I would add a simple Web project and configure it to host the Silverlight app. You'll need to host the app somewhere anyways, so why not create a stub ASP.NET application in your solution? The easiest way is to create a new Silverlight app solution selecting an ASP.NET web project as the host, and then copying your existing code to that solution. Then you should set the web project as the startup one. This should make debugging a lot easier.
Besides, do remember to configure the client access policy to enable cross-domain calls. Check out this article
We currently have a Silverlight application which is hosted in a SharePoint 2010 page. The Silverlight app makes web service calls to a another server on our domain, which has a clientaccesspolicy file in place. We are experiencing cross-domain issues in our production environment.
Users in the farm admin group can use the Silverlight application without any issues. However, all other users recieve the generic cross domain exception when they try to use this app. We have attached Fiddler to the process and noticed that the farm admins are served the clientaccesspolicy file, but that non-admin users are not. In fact, Fiddler does not ever show an attempt to load this file for non-admins.
This only happens in our production environment, which leads me to believe there is a web config or permission setting causing the issue. Unfortunately, I cannot find anything that backs this up.
Has anyone else run into this issue or know if such a setting exists?
See comments above. I had to change the URL to use the full machine name i.e. from webserver/service.svc to webserver.domain.com/service.svc. It solved the problem but doesn't answer the question about why the farm admins could access it. vorrtex's response is the best possible explanation I have seen so far.
This one has me completed stumped. I have developed a silverlight application that calls back to WCF services ( it's a silverlight - basicHttpBinding)
The site works perfectly fine from my development machine, but when it is deployed to the developement server. The application is delivered with the XAP just fine, but it never attempts to talk to the service. I have a service call in the bootstrapper so it should be calling this when the client starts up. The services are healthy. They can be browsed to and show the standard WCF service display. We have been through the bindings many times and everything seems to be ok. I have added an extensive amount of error handling for displaying any errors, but on this dev server, no service calls and no errors are being raised.
Fiddler shows the page being loaded up, but my client never issues a call to the service. The service is in the same folder as the default.aspx which hosts the Silverlight client.
This is a Silverlight 3.0 app.
Anybody ever seen anything similar?
I will try to debug in three steps
Verify whether the hosted service on dev server is up or not, by hitting the service URL from your browser on your dev machine.
Make sure that ServiceReferences.ClientConfig consists ur hosted service URL and not dev machine service URL.
If still error occurs try to debug your application from visual studio by pointing the endpoint address to http://urserver/urservicename.svc
Also make sure you dont have have cross domain problems by using "silverlight spy" tool
Put a graphical display like "I made the call!" before the service invocation. just to be sure that your app is really trying to call the service...
So we could narrow the search to a communication problem. : )
Verify that there aren't any cross-domain rules stopping the app to make the call.
by the way, are you calling a WCF service from another domain?
Are you sure the silverlight app is loading at all? If you are making the service call in the boot strapper and the call breaks, I assume that will lead to just a blank page. If you are seeing just a blank page, then perhaps there is something wrong with the .xap mime type issued from the server. Here is some more info on that:
http://learn.iis.net/page.aspx/262/configuring-iis-for-silverlight-applications/
I am using a silverlight with wcf and when I use the .web project then it runs but when use the silver light project to run the following exception throws:
An error occurred while trying to make a request to URI 'http://localhost:9000/Services/BLWCFSvrc.svc'. This could be due to attempting to access a service in a cross-domain way without a proper cross-domain policy in place, or a policy that is unsuitable for SOAP services. You may need to contact the owner of the service to publish a cross-domain policy file and to ensure it allows SOAP-related HTTP headers to be sent. This error may also be caused by using internal types in the web service proxy without using the InternalsVisibleToAttribute attribute. Please see the inner exception for more details.
I want to use the silverlight project to debug my code
Thanks in advance
In order to access network resources from Silverlight, the domain hosting the resource must provide a client access policy file; this is designed this way for security reasons. See here for details: http://msdn.microsoft.com/en-us/library/cc645032%28VS.95%29.aspx
I think your problem is different that just having the clientaccesspolicy.xml, the fact that it runs under the web project, means that you are delivering policies, if you have those added as seperate files under the web project then they wont be deployed when you run the SL3 app seperately, but im sure you figured this out and you're delivering the policies via WCF using webHttp binding (RESTful style), if not, you should.
I think the problem is that when you run the webproject, it builds to your local IIS and executes from there, IIS will allow the SL3 app to communicate with ports/addresses different from the ones that the site is hosted on
when you run SL3 app natively, VS2008 auto generates a test html site for it to be hosted in with some default settings, and uses VS2008 built-in hosting service, which does not allow communication to an address/port different from that of the hosting address. (even though Silverlight is a client side library, VS2008 can do this)
so if you want to run the Silverlight application natively, meaning actually executing the XAP, you can deploy it to IIS, and configure IIS to deliver XAP files, or just install it and run it out of browser and let it update from IIS the deployed version
Just copy a clientaccesspolicy.xml file (for an example take a look at this post; you can even use this sample) into the root of your webserver (eg: c:\inetpub\wwwroot\).
This should help.
I've got a Silverlight application which uses a built-in .ASMX WebService to access a SQL database and run some queries. Everything runs without any hitches on my Development machine.
I'm trying to deploy the application to IIS 6 and I'm having some issues.
The Silverlight application itself seems to run fine, however the Web Service does not. I get an unhandled exception error that says [Async_ExceptionOcurred] as soon as the page loads (when the page loads I'm making some Async WebService method calls).
I think this is an issue with the Web Service but I don't know what the problem is. I tried setting the WebService namespace to my URL, but that didn't work. I've tried messing with the SQL connection string in my Web Config but that also affects nothing.
One thing to note is that my IIS Virtual Directory only contains my SilverlightApp.Web folder. I know that the other folder that's part of the application contains a .ClientSettings file for the WebService, but I think this is embedded into the .xap.
Can anyone shed any light on this?
The most likely thing that's happening:
Your webservice proxy on the client is using the address of the web service it was built against: ("http://localhost...").
Things to do:
Use fiddler to confirm this is the issue. It will show you where the proxy is making the call to.
Use the overloaded constructor for the web service and specify a URI. Consider using id/deffing for debug/release. This will overwrite the settings in the client.config.
Create another endpoint in the client config for the release build (Shawn's article here) and select one or the other (again using if/defs).
There are other options as well (looking at the URI and building up the service adress)... but that's the general idea.
hth,
Erik