i'm writing a file importer and want to handle pdf types. i see the com.ado开发者_运维技巧be.pdf (kUTTypePDF
) and also public.composite-content
type.
Uniform Type Identifiers Reference docs :
Base type for mixed content. For example, a PDF file contains both text and special formatting data.
can someone kindly give an example of this type of file ?
The com.adobe.pdf
identifier inherits from public.composite-content
. In other words, PDF documents are a specific subset of all documents that conform to public.composite-content
.
As you can see in the reference documentation, there are many types that conform to public.composite-content
, such as com.apple.rtfd
(for RTF documents), com.apple.webarchive
and public.presentation
for presentation files (Keynote, Powerpoint etc).
The main distinguishing feature of public.composite-content
files is that they combine different specific types of data in one file, as opposed to types inheriting from public.data
which are just binary blobs. I personally think the distinction is not exactly clear-cut but there you go.
If you want to handle PDF types, you just need to declare conformance to com.adobe.pdf
.
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