Asp.net Webparts vs Sharepoint Webparts and SP 2007 Object Model Vs SP 2010

Choosing Between ASP.NET 2.0 Web Parts and Windows SharePoint Services 3.0 Web Parts

Office SharePoint Server 2007 and Windows SharePoint Services 3.0 are built on top of the ASP.NET 2.0 Framework. Windows SharePoint Services 3.0 uses the ASP.NET 2.0 Web Part infrastructure to take advantage of features such as master pages and custom Web Part development while providing a complete set of Windows SharePoint Services features, such as document services, events, workflow, search, site columns, content types and more.
You can build Web Parts for Windows SharePoint Services 3.0 in two ways:
* Create custom ASP.NET 2.0 Web Parts.
* Create SharePoint-based Web Parts.
Decision matrix for creating Web Parts
Create a custom ASP.NET 2.0 Web Part

· For most business needs.

· To distribute your Web Part to sites that run ASP.NET 2.0 or SharePoint sites.

· When you want to reuse one or more Web Parts created for ASP.NET 2.0 sites on SharePoint sites.

· To use data or functionality provided by Windows SharePoint Services 3.0. For example, you are creating a a Web Part that works with site or list data.

Create a SharePoint-based Web Part

· When you want to migrate a set of Web Parts using the SharePoint-based Web Part infrastructure to Windows SharePoint Services 3.0.

· To create cross page connections.

· To create connections between Web Parts that are outside of a Web Part zone.

· To work with client-side connections (Web Part Page Services Component).

· To use a data-caching infrastructure that allows caching to the content database.

SharePoint 2007 Lookup Column vs SharePoint 2010

Cascade Delete
SharePoint 2007: The Lookup column in SharePoint 2007 does not support cascade delete. i.e. if If an Item\Value in the the look-up list is deleted, then all those items referencing that value (as look-up value) will not be delete. This will rather present you with various errors and can also cause errors on the Site page if your are using one of them as filters.
SharePoint 2010: If an Item\Value in the the look-up list is deleted, then all those items referencing that value (as look-up value) in other lists will also be deleted.

Restrict Delete
SharePoint 2007: Does not have option to restrict deleting of lookup list items\values.
SharePoint 2010: Choosing this option would restrict the users from deleting an item in the column in the Look-up list, if the value is being used in some other lists.

Number of columns displayed
SharePoint 2007: This will only display the chosen lookup column in the referencing list.
SharePoint 2010: You can now display additional columns from the look-up list, along with the chosen lookup field.

SP 2007 Object Model Vs SP 2010

In Sharepoint Object model there are two Important namespaces.
In SharePoint 2007 - The Microsoft.Office.Server namespace is the root namespace of all Office Server objects and Microsoft.SharePoint is the root namespace for all WSS objects.
Hive:
In SharePoint 2007 - It has "12 hive" structure where all SharePoint resources are deployed.
In SharePoint 2010 - Microsoft has apparently added three new folders to its hive and calling it as "14 Hive"
* UserCode – files used to support sandboxed solutions
* WebClients – used for the client Object Model
* WebServices – New .svc files

Foundation :
SharePoint 2007 : Wss 3.0 was required for accessing all common SharePoint API's
SharePoint 2010 : SharePoint Foundation 2010 is required to provide base API's.

API's :
SharePoint 2007 : No API was available for Code to Interact with SharePoint site through Client side scripts (side Note : You can do it by calling Sharepoint web services using javascript )
SharePoint 2010 : MS has introduced Microsoft.SharePoint.Client namespace that enable you to interact with SharePoint sites through scripts that run in the browser from Microsoft .NET Framework managed code, and inside Microsoft Silverlight applications.