Managing Reference Attachments in MSG Files Using C#

AddingReferenceAttachments.cs

var options = new ReferenceAttachmentOptions(
    "https://drive.google.com/file/d/1HJ-M3F2qq1oRrTZ2GZhUdErJNy2CT3DF/", // Attachment URL
    "https://drive.google.com/drive/my-drive", // Provider link
    "GoogleDrive" // Provider type
);

// Add reference attachment
msg.Attachments.Add("Document.pdf", options);

IdentifyReferenceAttachmentsInMsgFiles.cs

var msg = MapiMessage.Load(@"message.msg");

foreach (var attachment in msg.Attachments)
{
    if (attachment.IsReference)
    {
        // Process reference attachment
    }
}

ReadingPropertiesOfReferenceAttachments.cs

var msg = MapiMessage.Load(@"message.msg");

foreach (var attachment in msg.Attachments)
{
    if (attachment.IsReference)
    {
        var originalUrl = attachment.GetProperty(KnownPropertyList.AttachmentOriginalUrl).GetString();
        var providerType = attachment.GetProperty(KnownPropertyList.AttachmentProviderType).GetString();
        var longPathname = attachment.GetProperty(KnownPropertyList.AttachLongPathname).GetString();
        var attachMethod = attachment.GetProperty(KnownPropertyList.AttachMethod).GetLong();

        Console.WriteLine($"Original URL: {originalUrl}");
        Console.WriteLine($"Provider Type: {providerType}");
        Console.WriteLine($"Long Pathname: {longPathname}");
        Console.WriteLine($"Attach Method: {attachMethod}");
    }
}