Android Question Extracting and decoding Base64 eMail Body

[William Hunter]

I have attached a raw email message encoded Base64. I would like to extract the message body, and then decode it to utf-8. There don't seem to be any tags to identify the beginning and end of the body, so I'm at a loss as to how to do this. The code below is for a Sub I have created to decode Base64, but it does not deal with extracting the body. Is there a way of doing this? Any help gretly appreciated.

Best regards

Sub Base64Decode(MyString As String) As String
   If Regex.Matcher2("^(?:[A-Za-z0-9+/]{4})*(?:[A-Za-z0-9+/]{2}==|[A-Za-z0-9+/]{3}=)?$", _
     Regex.CASE_INSENSITIVE, MyString).Find = True Then
     'Log("Base64Text")
     Try
       Dim su As StringUtils
       Dim Data() As Byte = su.DecodeBase64(MyString)
       MyString = BytesToString(Data, 0, Data.Length, "UTF8")
     Catch
       Log("LastException: " & LastException)
     End Try
   End If
   Return MyString
End Sub

 

[DonManfred]

. There don't seem to be any tags to identify the beginning and end of the body

The message has the following boundary.

----boundary_223389_fb6d2117-94ea-4f10-8100-eaf0eda49579

This is the splitpoint of the parts of the mail.
The first is the textpart, the second the html-part

----boundary_223389_fb6d2117-94ea-4f10-8100-eaf0eda49579
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: base64

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DQpUaGFuayB5b3Uh
----boundary_223389_fb6d2117-94ea-4f10-8100-eaf0eda49579
Content-Type: text/html
Content-Transfer-Encoding: base64

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----boundary_223389_fb6d2117-94ea-4f10-8100-eaf0eda49579--

 

[William Hunter]

The message has the following boundary.

This is the splitpoint of the parts of the mail.
The first is the textpart, the second the html-part

----boundary_223389_fb6d2117-94ea-4f10-8100-eaf0eda49579

Thank you DonManfred. Yes, I know the boundaries are there, but the MailParser doesn't recognize them. When parsed this message comes through as a 0 byte file. In an earlier post Erel has stated that the MailParser is specifically not compatible with multipart/alternative, so the result is not unexpected. I am trying to find a way to display this type of message in a WebView by extracting the text part for the body by some other means, and then decoding it. I haven't even thought of trying to decode the html. Do you have any other thoughts?

Best regards

 

[Erel]

I've just tested MailParser with the mail you posted and it parses this email successfully.

It treats each part as an attachment:

Dim m As Message = MailParser.ParseMail(File.ReadString(File.DirAssets, "RawMailLibrary.txt"), File.DirInternal)
For Each s As String In m.Attachments
   Log(File.ReadString(File.DirInternal, s))
Next