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JavaScript

Fetch 1st N Headers of Search Results

Calls Search to get a message set, then downloads the 1st N messages in the message set. There are two equivalent ways of doing it: (1) iterate from 0 to N-1 and download each message individually, or (2) create a new message set that contains the 1st N messages and pass it to FetchHeaders. Both are demonstrated here.
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
var success = false;

// This example assumes the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

var imap = new CkImap();

// Connect to an IMAP server.
// Use TLS
imap.Ssl = true;
imap.Port = 993;
success = imap.Connect("imap.example.com");
if (success == false) {
    console.log(imap.LastErrorText);
    return;
}

// Login
success = imap.Login("****","****");
if (success == false) {
    console.log(imap.LastErrorText);
    return;
}

// Select an IMAP mailbox
success = imap.SelectMailbox("Inbox");
if (success == false) {
    console.log(imap.LastErrorText);
    return;
}

// Get the message IDs of all the emails in the mailbox
// We can choose to fetch UIDs or sequence numbers.
var fetchUids = true;
var messageSet = new CkMessageSet();
success = imap.QueryMbx("ALL",fetchUids,messageSet);
if (success == false) {
    console.log(imap.LastErrorText);
    return;
}

var numFound = messageSet.Count;
if (numFound == 0) {
    console.log("No messages found.");
    return;
}

// Get the 1st 10 messages in messageSet.
var upperBound = 10;
if (numFound < upperBound) {
    upperBound = numFound;
}

var i = 0;
var bUid = messageSet.HasUids;
var headerOnly = true;
var email = new CkEmail();

while (i < upperBound) {

    success = imap.FetchEmail(headerOnly,messageSet.GetId(i),bUid,email);
    if (success == false) {
        console.log(imap.LastErrorText);
        return;
    }

    console.log(i + ": " + email.Subject);

    i = i+1;
}

// Disconnect from the IMAP server.
success = imap.Disconnect();