Description
object 
imap_fetchstructure ( resource imap_stream, int msg_number [, int options])
     This function fetches all the structured information for a given
     message. The optional options parameter only
     has a single option, FT_UID, which tells
     the function to treat the msg_number
     argument as a UID. The returned object
     includes the envelope, internal date, size, flags and body
     structure along with a similar object for each mime
     attachment. The structure of the returned objects is as follows:
    
     
表格 1. 
       Returned Objects for imap_fetchstructure()
      
| type | Primary body type | 
| encoding | Body transfer encoding | 
| ifsubtype | TRUE if there is a subtype string | 
| subtype | MIME subtype | 
| ifdescription | TRUE if there is a description string | 
| description | Content description string | 
| ifid | TRUE if there is an identification string | 
| id | Identification string | 
| lines | Number of lines | 
| bytes | Number of bytes | 
| ifdisposition | TRUE if there is a disposition string | 
| disposition | Disposition string | 
| ifdparameters | TRUE if the dparameters array exists | 
| dparameters | An array of objects where each object has an "attribute" and a
         "value" property corresponding to the parameters on the
         Content-disposition MIMEheader. | 
| ifparameters | TRUE if the parameters array exists | 
| parameters | An array of objects where each object has an "attribute" and
         a "value" property. | 
| parts | An array of objects identical in structure to the top-level
         object, each of which corresponds to a MIME body
         part. | 
     
表格 2. Primary body type
| 0 | text | 
| 1 | multipart | 
| 2 | message | 
| 3 | application | 
| 4 | audio | 
| 5 | image | 
| 6 | video | 
| 7 | other | 
     
表格 3. Transfer encodings
| 0 | 7BIT | 
| 1 | 8BIT | 
| 2 | BINARY | 
| 3 | BASE64 | 
| 4 | QUOTED-PRINTABLE | 
| 5 | OTHER | 
     See also: imap_fetchbody().