Types of Custom Webparts in MOSS 2007

What is Webpart?

A web part is an ASP.NET server control which is added to a Web Part Zone on Web Part Pages by users at run time. Web Parts are an integrated set of controls for creating Web sites that enable end users to modify the content, appearance, and behavior of Web pages directly from a browser. The Web Parts control set is a group of components that work together to enable developers to create Web pages where users can modify the user interface (UI) directly from a browser. The UI controls all derive from the WebPart class, and they compose the primary UI on a Web Parts page.

Basically, Web Parts are Microsoft’s version of Widgets

Web Parts can be used as add-on ASP.NET technology to Windows SharePoint Services.

Types of Webparts

1. ASP.net Webpart (System.Web.UI.WebControls.WebParts)

2. WSS Webpart (Microsoft.SharePoint.WebPartPages.WebPart)

3. Hybird Webpart (Microsoft.SharePoint.WebPartPages.WebPart)

1. ASP.net Webpart

ASP.WebPart derives directly from the ASP.WebPart class which does not have a dependency on Windows SharePoint Services 3.0 code so it can be used in both ASP.NET Web sites or a Windows SharePoint Services 3.0 site collection/Web. To ensure the Web Part customization is sustainable you should consider using the ASP.WebParts. ASP.WebParts are exportable using the .webpart extension, can be displayed in SPD using attribute markup and are persisted to the Windows SharePoint Services store in binary Web Part format

2. WSS Webpart

WSS Web Parts derive from the WSS.Web Part base class and meet the guidelines as provided by the Windows SharePoint Services 2.0 Web Part design guidelines. The WSS.WebPart class is obsolete and is retained solely for backwards compatibility. Wss.WebParts are exportable using the .dwp extension, can be displayed in SPD using XML Markup and are persisted to the WSS store in a compressed XML format

3.Hybird Webpart

Hybrid web parts, just like classic WSS web parts, inherit from Microsoft.SharePoint.WebPartPages.WebPart.Hybrid web parts use ASP.NET 2.0 web part development techniques and capabilities combined with WSS capabilities. Hybrid Web Parts can also be used in version to version upgrades where the existing legacy hybrid Web Part cannot be retired in favor of a ASP.WebPart. Hybrid Web Parts are exportable using the .webpart extension, can be displayed in SPD using attribute markup and are persisted to the Windows SharePoint Services store in binary Web Part format.

Why Hybird Webpart?

I am not sure how popular creating hybrid web parts will be, but people would want to create hybrid web parts for migration purposes. You could create a web part now in 2003 and combine base WSS capabilities with modern ASP.NET web part development techniques, making a hybrid web part operate like a normal ASP.NET 2.0 web part. Such a web part would be easy to migrate to 2007.

More about hybird webpart… Click here

[REF-MSDN]