10. A computer storage medium having computer readable instructions stored thereupon that, when executed by a computer, cause the computer to: execute an application program of a plurality of application programs configured to expose a set of application programming interfaces for interacting with a file associated with the application program; initialize, via the set of application programming interfaces, an extension object for supplementing functionality of the application program; identify a section of the file, the section being identified as a generic data type that is applicable to individual ones of the plurality of application programs; access the section via the set of application programming interface interfaces; and perform an operation on the section by presenting a user interface for selecting a portion of the file, wherein the user interface is configured to allow a user to select the portion of the file and to return the selected portion of the file to the extension object for use as a binding.
10. A computer storage medium having computer readable instructions stored thereupon that, when executed by a computer, cause the computer to: execute an application program of a plurality of application programs configured to expose a set of application programming interfaces for interacting with a file associated with the application program; initialize, via the set of application programming interfaces, an extension object for supplementing functionality of the application program; identify a section of the file, the section being identified as a generic data type that is applicable to individual ones of the plurality of application programs; access the section via the set of application programming interface interfaces; and perform an operation on the section by presenting a user interface for selecting a portion of the file, wherein the user interface is configured to allow a user to select the portion of the file and to return the selected portion of the file to the extension object for use as a binding. 12. The computer storage medium of claim 10 , further comprising computer readable instructions that, when executed by the computer, cause the computer to: set the binding for the section of the file, the binding comprising data identifying a bound section of the file; determine if the portion of the file is selected; and in response to determining that the portion of the file is selected, writing at least one of portion data from the portion to the bound section, or bound section data from the bound section to the portion.