Microsoft Office Tutorials and References
In Depth Information
Chapter 14: Building Custom Solutions
The Excel Services web service is fairly straightforward and easy to use. Understanding some of the
Excel Services concepts can help you get more out of the API methods. This section draws attention to
parameters and concepts that are standard across the majority of the API methods.
Each time Excel Services opens a workbook, a new session is created. Each created session has an
associated session ID that is unique. The session ID becomes a key for the Excel Services web service methods
to perform operations on the caller’s session, and maintain state for the life of the session. To perform
any operation on the workbook using an API method, a valid session ID is required, which implies that
the session is still active.
A session ends when the API CloseWorkbook method is called. A session can also time out after a period
of inactivity, or be forced to time out prematurely under some Excel Calculation Server (ECS)
errorhandling conditions. Use the Excel Services administration settings to configure the session timeout
associated with inactivity.
A session ID is a string that is similar to the following, which is a composite ID built with components
such as the data culture and UI culture from the OpenWorkbook method call, time zone details, and an
internal ECS session ID:
The data culture is equivalent to the configurable SharePoint site locale ID. The data culture specifies the
language culture to be used when formatting numbers, currencies, and dates.
The UI culture is equivalent to the SharePoint site language ID. The UI culture specifies the language
culture to be used for menus, drop-down lists, toolbars, and error messages. An Excel Services web service
method uses the UI culture for error messages being returned to the method caller.
Both the data culture and the UI culture are set on each session created by the API OpenWorkbook method,
and those culture settings are used for the life of the session. Excel Services supports the same set of
languages that is supported by Microsoft .NET Framework version 2.0. The .NET Framework package
includes the System.Globalization namespace, which contains the CultureInfo class that can
provide the supported cultures. Neutral culture languages are not supported by Excel Services for data
cultures. A neutral culture is one that is expressed in the form of en instead of en-us , for example. A
neutral culture is handled by Excel Services as an unsupported data culture.
Excel Services defaults to a fallback culture for both the data culture and the UI culture when an
unsupported or uninstalled culture is used by an API method call. If the fallback culture logic is invoked by
Excel Services, the API method’s out Status parameter provides the information about the culture