Asp.net 3.0 or Asp.net 4.0? new Project

We are starting developing new web-based application in weeks times.

Which version of asp.net would you guys recommend. ASP.NET 3.0 or ASP.NET 4.0 (visual studio 2008 or Visual studio 2010)?

Previously we have worked on ASP.NET 2.0 using visual studi开发者_如何学Co 2005

Same with sql server should we keep using sql server 2005 or migrate it to sql server 2008

If you are starting a new project and you don't intend to use third party libraries that are not compatible with .NET 4.0 then go for ASP.NET 4.0 (Choose Visual Studio 2010 as 2008 cannot target .NET 4.0). As far as SQL Server is concerned, because this is a migration you might need to first analyze what would be the possible impacts on your current infrastructure.

If you have the tools available, and you host the site yourself (not paying a 3rd party hoster) than there is no reason to not use VS2010 and .net 4. If you do have a 3rd party host the site, they may not yet support .net 4.

At the very least, you should use VS2010 and target .net 3.5. That way when you are ready to go to .net 4, it will be an easier switch.

Agreed. If you have the tools, definitely go with 4.0.

1. VS 2010 is great.
2. If you start a new project with moderately out-dated tools, you'll soon find that you are maintaining a project with very out-dated tools. Start with the latest stable tools and you push out your upgrade costs a little further.

I would say generally that the same goes for SQL Server. Assuming you have no licensing problems or existing infrastructure, go with the latest version. SQL Server 2008 was not nearly as big an upgrade as VS 2010. You won't have any trouble with a transition to the new tools, etc.