Silverlight 3 Upgrade from Silverlight 2 and FireFox Anomaly

10-29-2009 7:03 AM |

Greets,

I hope that I can help others who may be having problems with: a) upgrading Silverlight 2 applications to Silverlight 3 and b) an issue we discovered with FireFox 3.5 which caused some inexplicable behavior.

First, some words of advice when 'automagically' upgrading (through the Visual Studio 2008 upgrade wizard):

1) for any Web test harnesses (i.e. the ProjectName.Web that you may choose to create) delete your test ASPX and HTML pages that are generated for  you.  Go into the project properties under the Silverlight section, remove the Silverlight project and re-add.  It will regenerate the pages using the <object /> tag.  Also, ensure that you replace your Silverlight.js JavaScript file with the latest version.  (Remember to upgrade your Default.aspx page if you've modified that as well.)  We had an old Silverlight.js file which kept the application from appearing on certain browsers (such as Safari);

2) check your references carefully.  In cases where we were using a DataGrid, we needed to remove the existing assembly reference and re-reference the new Silverlight 3.0 assembly that contained the updated DataGrid; and

3) if for any reason you have modified the <object /> tag in order to add the "initParams" node, make sure that it is not empty.  (i.e. avoid <param name="initParams" value="" />)  For some reason, this caused our application to continue to show the "Get Silverlight" badge in FireFox 3.5 in order to download the plug-in which was already installed.  In our case, we were passing the ClientQueryString through a clever bit of ASP.NET code; however, it was empty on initial load-up which caused the issue.  We worked around this by checking the length of the query string and in the case where the length was greater than '0', we would Response.Write() out the <param /> tag, otherwise, just left it out.  Hopefully this will be corrected soon.

For the most part, our transition to Silverlight 3 was fairly painless, but our applications weren't that complex to cover many of the breaking changes that existed.  However, hopefully this information can spare someone a little pain.

Regards,

Joe

Re: Silverlight 3 Upgrade from Silverlight 2 and FireFox Anomaly

11-03-2009 12:39 AM |

Hi Joe,

Thanks for sharing, this thread would be helpful for someone who encountered problem with silverlight in Firefox browser. I'll keep this thread in my favorites.