Moss content types Overview

About the content types of moss 2007

1. Overview

In wss2.0, a list is defined by a set of required fields applied to each list item of the list. having a single set of fields means that each list item is closely related to its location. all list items at a location can only be associated with the columns defined for the list or document library. in wss3.0, list contains multiple architectures in the form of content types. content type provides the encapsulated data schema and its independent location on the SharePoint site. conent type helps users organize documents and other materials stored on SharePoint sites. for developers, a content type provides a way to define and use meatadata to differentiate the types of each list item. A content type is a set of meatadata and settings, which are applied to a certain type of list content. for example, a content type called specifications can contain these columns, such as project, priority, developer, and testleader. A content Tye called contract uses fields such as approver, signed, and amount. even with these differences, specifications and contracts can be listed in the same list or document library.

Because content type is independent from a specific list or document library, a content type can be used in lists on multiple SharePoint sites. in this way, the content types stored in the site collection can be defined and managed in a more centralized manner. A content type can be extended by defining similar workflow and custom attributes.

2. file formats:

Content types is independent of the file format. in the document library, you can specify a document template for a content type. when you create a document of this type, WSS uses this template. you can still upload a document based on different templates to the document library.

For example, if you create a content type that is applied to the documents required by a project ,. this project content type can be applied to any file format, including Word documents containing project planning information, Excel documents containing project budgets, Microsoft Project documents for planning, and a Sharepoint list item that stores the project team member name and role. all these files and list items can be assigned to the project content type.

3. Site and list content types

The content type created on site level is called site content type. any sub-site can inherit a content type. if a content Tye is created on the Root site of the site collection, any site under it can inherit the content type.

After a content Tye is added to the List, WSS stores a local copy of the content Tye in the list. this local instance is called a list content type, which is only applied to the list copied. because the changes to such a list content type instance do not affect the site content type itself.

4. creating content types based on other content types

You can create content types based on other content types. using this relationship, you can create a general content type that contains other different content type attributes, and then inherit from these general content types to generate more specific content types. under site level, you can create site content based on other site content types. in list level, you can create list content based on other site content types.

You can edit the attribute of site content type inherited from another site content type by adding, deleting, and modifying columns.

In WSS, the base content type hierarchy corresponds to the created type. When a list is created, WSS is based on the list content type of the appropriate base site content type.

5. Extending content types

Each content type has an XML file set, which can be used by third parties to save custom settings. developers can use XML files to extend the definition and functions of content Tye. the XML file contained in a site content type is copied to any subtype. if you modify an XML file and perform the push-down operation, the entire XML file in any sub-content type will be overwritten.

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Http://www.cnblogs.com/songzhenqian/archive/2006/07/12/448853.html