Using Flex and Silverlight in ArcGIS 9.3 and 10

[JoannaLaroussi]

I have to develop a web service and I need to decide between learning/using Flex and Silverlight. For now I have ArcGIS 9.3 but I am expecting to migrate to 10 in another couple of months.  I would like to choose program, which will work in both versions, so the later transition do not cost me starting from the scratch. I saw on server functionality matrix that Flex works with both versions, but it is possible to just take Flex developed for 9.3 and move it to 10? What about Silverlight? May I use Silverlight in 9.3 in the same way as in 10? Thanks for all your responses!

[AniketWani]

ArcGIS Flex API 2.x is backward compatible i.e. you can use it with ArcGIS server 10 as well as with ArcGIS server 9.3.1.

You can start with ArcGIS Flex API latest version which is 2.1 now. You don't have do any major code changes when you migrate to ArcGIS server 10 except few for performance improvement which are optional.

Here you can read about System requirements of Flex API 2.x - http://help.arcgis.com/en/webapi/flex/help/index.html#references/system_requirements.htm#

Link to download Flex API 2.1 - http://resources.arcgis.com/content/arcgis-flex-api-how-to-download

[JoannaLaroussi]

Thank you for your explanations!