email.iterators ：迭代器

源代码： Lib/email/iterators.py

Iterating over a message object tree is fairly easy with the Message.walk 方法。 email.iterators module provides some useful higher level iterations over message object trees.

email.iterators. body_line_iterator ( msg , decode = False )

This iterates over all the payloads in all the subparts of msg , returning the string payloads line-by-line. It skips over all the subpart headers, and it skips over any subpart with a payload that isn’t a Python string. This is somewhat equivalent to reading the flat text representation of the message from a file using readline() , skipping over all the intervening headers.

可选 decode 被传递给 Message.get_payload .

email.iterators. typed_subpart_iterator ( msg , maintype = 'text' , subtype = None )

This iterates over all the subparts of msg , returning only those subparts that match the MIME type specified by maintype and subtype .

注意， subtype is optional; if omitted, then subpart MIME type matching is done only with the main type. maintype is optional too; it defaults to text .

因此，默认情况下 typed_subpart_iterator() returns each subpart that has a MIME type of text/* .

The following function has been added as a useful debugging tool. It should not be considered part of the supported public interface for the package.

email.iterators. _structure ( msg , fp = None , level = 0 , include_default = False )

Prints an indented representation of the content types of the message object structure. For example: 

>>> msg = email.message_from_file(somefile)
>>> _structure(msg)
multipart/mixed
    text/plain
    text/plain
    multipart/digest
        message/rfc822
            text/plain
        message/rfc822
            text/plain
        message/rfc822
            text/plain
        message/rfc822
            text/plain
        message/rfc822
            text/plain
    text/plain