Application Data Storage
WHAT’S IN THIS CHAPTER?
- Understanding common application storage scenarios
- Using isolated storage on WP7
- Using external storage
Application data comes from various sources, such as user-generated inputs, operating system data, data received from the Web, and application-produced data. Some of the application data is transient, and you don’t need to save it in persistent storage, such as a Secure Digital (SD) card or device memory, or to save it on the Web; but other data may need to be persisted either in local data storage or to the Web so the application can access it later. This chapter shows how to leverage local data storage on the device and cloud storage (data storage on the Web, accessed via web services) on WP7 to save persistent data. After reading this chapter, developers will be able to choose between local data storage and cloud storage to implement common data storage scenarios.
APPLICATION STORAGE ON MOBILE DEVICES
Generally, you have control over a few data storage design decisions when creating a mobile application:
- Where to save the data
- What format to save the data in
- How data is shared between applications
Historically, mobile applications on major software platforms usually have saved data locally on the device. For example, on Windows Mobile devices an application can use the registry to save some application-specific settings and use filesystem APIs to save other data to either device memory or an SD card. The iPhone ...