Filter and Paginate MBOX Emails in C#

CombineMessageFilteringAndPagination.cs

var reader = MboxStorageReader.CreateReader("input.mbox", new MboxLoadOptions());

// Filter: messages from a specific domain and sent this year
var mqb = new MailQueryBuilder();
mqb.From.Contains("@example.com");
mqb.SentDate.Since(new DateTime(DateTime.Today.Year, 1, 1));

var query = mqb.GetQuery();

// Page through message info (metadata only)
int pageSize = 5;
int index = 0;
bool done = false;

while (!done)
{
    var page = reader.EnumerateMessageInfo(query).Skip(index).Take(pageSize).ToList();

    if (page.Count == 0)
        break;

    foreach (var info in page)
    {
        Console.WriteLine($"Subject: {info.Subject}, From: {info.From}, Date: {info.Date}");
    }

    index += pageSize;
    done = page.Count < pageSize;
}

FilterMboxMessagesBySubjectAndDate.cs

var reader = MboxStorageReader.CreateReader("input.mbox", new MboxLoadOptions());

// Build a query: subject contains "Project Update" and sent before today
var mqb = new MailQueryBuilder();
mqb.Subject.Contains("Project Update");
mqb.SentDate.Before(DateTime.Today);

var query = mqb.GetQuery();

// Enumerate and display filtered messages
foreach (var message in reader.EnumerateMessages(query))
{
    Console.WriteLine("Subject: " + message.Subject);
    Console.WriteLine("Date: " + message.Date);
    Console.WriteLine("From: " + message.From);
    Console.WriteLine(new string('-', 40));
}

PaginateLargeMboxFiles.cs

var reader = MboxStorageReader.CreateReader("input.mbox", new MboxLoadOptions());

int pageSize = 10;
int currentIndex = 0;
bool hasMore = true;

while (hasMore)
{
    var messages = reader.EnumerateMessages(currentIndex, pageSize);
    int count = 0;

    foreach (var message in messages)
    {
        Console.WriteLine($"[Message {currentIndex + count + 1}] Subject: {message.Subject}");
        count++;
    }

    if (count < pageSize)
        hasMore = false; // No more messages

    currentIndex += pageSize;
}