Content type

Content types are a powerful new enhancement introduced in WSS 3.0. The central idea is that a content type defines the underlying schema for either an item in a list or a document in a document library. However, it’s important to understand that content types are defined independently outside the scope of any list or document library. After you have created a content type, you can use it across several different lists or several different document libraries.

How to create site column

Site column is a reusable elements to build a content type or define a list. For example, if you have lots of lists which is using zip code, instead of redefining the zip code in all the lists, you can create a zip code site column so that you can use it across all the lists. Here site column and field type means the same thing, it is like int or string in .net. But it also can have some logic or UI associate with it.There are three ways to build a site column or field types.

CAML Debugging Through Diagnostic Logging

CAML content definitions have no debugging support through Visual Studio. This can make it frustrating to develop custom content types, lists, and other provisioning components. You can, however, enable verbose logging through SharePoint Central Administration. From the Operations tab, under Logging and Reporting, select Diagnostic Logging. You can then set Event Throttling to report on all categories, to report on events of information criticality and above, and to report verbosely. For a personal development server, you can use just one log file for a period of ten minutes. The default path for the logs is C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\12\LOGS. You may want to import the log into Microsoft Office Excel 2007 or just use Visual Studio or Notepad to read the file.

SPGridView

SharePoint has some very useful controls defined in the Microsoft.SharePoint.WebControls namespace that extend common ASP.NET controls with the SharePoint functionality and look and feel. Perhaps the most useful Web control is SPGridView. The SPGridView control extends the ASP.NET GridView class with SharePoint’s style declarations and has additional support for WSS data sources such as Lists and Cross-Site Queries using the SPDataSource class.

Dynamic Master Page , Application Page's Master Page

In sharepoint, the content page can use a master page like below.

<%@ Page language="C#" MasterPageFile="~masterurl/default.master"    Inherits="Microsoft.SharePoint.WebPartPages.WebPartPage,Microsoft.SharePoint,Version=12.0.0.0,Culture=neutral,PublicKeyToken=71e9bce111e9429c" meta:webpartpageexpansion="full" meta:progid="SharePoint.WebPartPage.Document" %>

When MasterPageFile attribut is either "~masterurl/default.master" or "~masterurl/custom.master", the master page is dynamic master page, in this case you don't need to modify the content page to change its master page, master page is dynamically determined by two site property, "MasterUrl" or CustomMasterUrl. If you specify other values, then master page is bound.