Download email attachments in .NET
First you’ll need an IMAP client or POP3 client to download emails from the server.
The email attachments are downloaded as a part of the message. Attachments are stored within the email as part of a mime tree. Usually Quoted-Printable or Base64 encoding are used. Mail.dll is going to parse such tree for you and expose all attachments as well known .NET collections.
IMail uses 3 collections for storing attachments:
- Attachments - contains all attached documents
- Visuals - contains files that should be ‘displayed’ to the user (like images or music that should be played in background)
- NonVisuals - contains attachments that should not be ‘displayed’ immediately
Following you’ll find samples of how you can save all attachments to disk using C# and VB.NET via POP3 and IMAP protocols.
When you use IMAP server:
// C# version
using(Imap imap = new Imap())
{
imap.Connect("server"); // or ConnectSSL
imap.UseBestLogin("user", "password");
imap.SelectInbox();
List<long> uids = imap.SearchFlag(Flag.All);
foreach (long uid in uids)
{
string eml = imap.GetMessageByUID(uid);
IMail email = new MailBuilder()
.CreateFromEml(eml);
Console.WriteLine(email.Subject);
// save all attachments to disk
email.Attachments.ForEach(mime => mime.Save(mime.SafeFileName));
}
imap.Close();
}
You can also save attachment to stream: void MimeData.Save(Stream stream)
Or get direct access to it: MemoryStream MimeData.GetMemoryStream()
' VB.NET version
Using imap As New Imap()
imap.Connect("server") ' or ConnectSSL
imap.UseBestLogin("user", "password")
imap.SelectInbox()
Dim uids As List(Of Long) = imap.SearchFlag(Flag.All)
For Each uid As Long In uids
Dim eml As String = imap.GetMessageByUID(uid)
Dim email As IMail = New MailBuilder()_
.CreateFromEml(eml)
Console.WriteLine(email.Subject)
' save all attachments to disk
For Each mime As MimeData In email.Attachments
mime.Save(mime.SafeFileName)
Next
Next
imap.Close()
End Using
When you use POP3 server:
// C# version
using(Pop3 pop3 = new Pop3())
{
pop3.Connect("server"); // or ConnectSSL
pop3.UseBestLogin("user", "password");
foreach (string uid in pop3.GetAll())
{
IMail email = new MailBuilder()
.CreateFromEml(pop3.GetMessageByUID(uid));
Console.WriteLine(email.Subject);
// save all attachments to disk
email.Attachments.ForEach(mime => mime.Save(mime.SafeFileName));
}
pop3.Close();
}
' VB.NET version
Using pop3 As New Pop3()
pop3.Connect("server") ' or ConnectSSL
pop3.UseBestLogin("user", "password")
For Each uid As String In pop3.GetAll()
Dim email As IMail = New MailBuilder() _
.CreateFromEml(pop3.GetMessageByUID(uid))
Console.WriteLine(email.Subject)
' save all attachments to disk
For Each mime As MimeData In email.Attachments
mime.Save(mime.SafeFileName)
Next
Next
pop3.Close()
End Using
June 7th, 2010 at 14:34
Is it possible for me to delete specified email with this component?
Thank You
June 8th, 2010 at 13:19
@Vincentius Yes, you can. Both IMAP and POP3 clients have two methods: DeleteMessage and DeleteMessageByUID.
If you are using GMail you may want to also check this post:
http://www.lesnikowski.com/blog/delete-email-permanently-in-gmail/
September 19th, 2010 at 20:47
When i try the “when using pop3 sever” for C# and i keep getting the System.UnauthorizedAccessException was unhandled error. Any fixes?
September 20th, 2010 at 12:35
@Franz
1. Are you using the latest version?
2. What is the stack trace of the exception?
3. Please contact us via email:
http://www.lesnikowski.com/contact/
it’ll be much easier to help you.
December 3rd, 2010 at 12:20
email.Attachments.ForEach(mime => mime.Save(mime.SafeFileName));
“=>” showing error
December 19th, 2010 at 12:36
@madhan
Lambda expressions are supported in C# compiler 3.0 or greater .
You can use regular foreach loop to iterate over Attachments collection.
December 19th, 2010 at 13:42
Hi,
Where I can change folder path for download attachments from POP3?
What is default path?
It’s working but i can’t able to see the download attachemnts
Please replay
December 20th, 2010 at 12:45
@Sunil
Attachments are part of the email you download, files are not created on disk until you call MimeData.Save method on objects in Attachments collection.
If you want to specify different folder than the default path for current process, just specify it as an argument for the Save method:
mime.Save(@”c:attachments” + mime.SafeFileName)
April 25th, 2011 at 09:41
Hi,
I want to download .csv format file and save it to database.
so how can i do it ???
I dont want to save the csv format file in any harddrive.
Please Reply.
April 25th, 2011 at 11:33
@Chintan
If the csv file is attached to the email you can directly access attachmentâs data as stream using MimeData.GetMemoryStream() method:
or as byte array using MimeData.Data property:
If your csv attachment has correct mime type, you can also cast MimeData to MimeText and use Text property to access csv data as string:
As for your question on how to save this data to database, it depends on the db you are using (MSSQL, Oracle, MySql, document db) and it’s structure. I don’t think I can help you with so little information you provided and also I believe it’s out of scope of Mail.dll.
July 13th, 2011 at 15:11
How can I check if the password that a user has entered matches to its username (basically if it is correct)…..
Thanks,
Binis
July 16th, 2011 at 09:09
@Binis Server does that.
If the password is incorrect you’ll get an exception from Login method.
August 16th, 2011 at 16:43
What if there are multiple files in the emails, I cannot figure out how to save them all?
Thanks,
Kent
August 16th, 2011 at 21:57
@Kent
You should iterate over Attachments collection as shown in the blog post,
you can use foreach loop if you are not familiar with lambdas:
foreach (MimeData attachment in email.Attachments) { attachment.Save("c:\" + attachment.SafeFileName); }October 3rd, 2011 at 12:30
files don’t save completely, size of downloaded files is zero.
October 4th, 2011 at 17:25
@mojtaba
Please be more specific. If you have problems parsing the message please follow the steps here: http://www.lesnikowski.com/blog//i-have-problems-parsing-the-message and contact us directly.
October 15th, 2011 at 20:06
I purchased your mail.dll, it’s awsome, But Why downloaded visual image saved in .DAT extension, is there any way to save it in proper extension
October 16th, 2011 at 12:41
@Veincorp
Most likely the sender of the message have not specified the filename at all.
In such case SafeFileName property (which you probably use with Save method) generates unique filename.
You can of course check FileName property for null and act according to your needs.
October 19th, 2011 at 14:41
I have set up a IMAP gmail account
I am trying to connect with the code :
using (Imap imap = new Imap())
{
imap.Connect(“smtp.gmail.com”);
imap.UseBestLogin(“imap.dmtrigger@gmail.com”, “password”);
imap.SelectInbox();
….
….
But I get this error :
“A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond …. ”
Would this be the problem with the account ? But I can send and recieve mails from the account I have set up in my Outlook.
Can anyone help?
Thanks,
Lax.
October 19th, 2011 at 22:11
@Lax,
1. When using IMAP protocol use IMAP server: imap.gmail.com
2. Use SSL
using (Imap client = new Imap()) { client.ConnectSSL("imap.gmail.com"); client.Login("user@gmail.com", "password"); client.SelectInbox(); // ... client.Close(); }