JavaScript

Get the Size of a POP3 Message by UIDL

Demonstrates the Chilkat MailMan.GetSizeByUidl method, which returns the size, in bytes, of the email on the POP3 server identified by a UIDL. The size includes the full message content, including attachments, and the method returns -1 on error. This example looks up a message's size by its UIDL.

Background: A UIDL ("unique ID listing") is POP3's stable identifier for a message — it stays the same across sessions as long as the message remains in the mailbox. Checking a message's size before downloading lets a client skip or defer very large messages, enforce size limits, or show a progress estimate. You can obtain the available UIDLs from GetMailboxInfoXml or FetchUidls.

Note

This example is intended for running within a Chilkat.Js embedded JavaScript engine. All Chilkat JavaScript examples require Chilkat v11.4.0 or greater.

JavaScript

//  Demonstrates the MailMan.GetSizeByUidl method, which returns the size, in bytes, of the
//  email on the POP3 server identified by a UIDL.  The size includes the full message
//  content, including attachments.  Returns -1 on error.

var mailman = new CkMailMan();

//  Configure the POP3 server connection.
mailman.MailHost = "pop.example.com";
mailman.MailPort = 995;
mailman.PopSsl = true;
mailman.PopUsername = "user@example.com";
mailman.PopPassword = "myPassword";

//  Get the size of a specific message by its UIDL.
var sizeBytes = mailman.GetSizeByUidl("0000000123abcdef");
console.log("Message size (bytes): " + sizeBytes);

//  Note: Explicitly connecting/authenticating is optional.  Chilkat MailMan automatically
//  connects and authenticates -- using the property settings above -- whenever a server
//  operation requires it.  Calling the explicit connect/authenticate methods can still be
//  helpful to determine whether a failure occurs while connecting or while authenticating.