Extracting email subject lines from Gmail using C# API

Other Questions Gmail
1

I’m working on a C# desktop application that needs to retrieve all emails from a Gmail account. Right now I can successfully get the email content but I’m struggling to figure out how to extract the subject lines instead.

Here’s what I have so far:

UsersResource.MessagesResource.ListRequest msgRequest = gmailService.Users.Messages.List("me");
IList<Google.Apis.Gmail.v1.Data.Message> messages = msgRequest.Execute().Messages;

foreach(var msg in messages)
{
    // currently getting message preview text
    Console.WriteLine("{0}", msg.Snippet);
}

This code works fine for getting the message preview, but I need to access the actual subject line of each email. How can I modify this to get the subject field instead of the snippet? Thanks for any help!

2

You’re only getting basic message data right now. To get the subject line, you need to fetch full message details for each email. The initial list request doesn’t include headers by default, so you’ll need an extra API call using the Get method for each message ID. Then parse through the headers to find the ‘Subject’ one. Try: var fullMessage = gmailService.Users.Messages.Get('me', msg.Id).Execute(); then loop through fullMessage.Payload.Headers looking for header.Name == 'Subject'. Just heads up - this’ll burn through your API quota fast since you’re making multiple calls.

3

there’s another way - use the metadata format with Messages.Get and the right parameters. try gmailService.Users.Messages.Get("me", msg.Id).Execute() but set format to METADATA first. then access message.Payload.Headers and find where header.Name.Equals("Subject"). way cleaner than full message fetches.

4

The Messages.List endpoint only gives you basic stuff like ID and snippet by default. To get subject lines, you need to tweak your request. Add the fields parameter to specify what data you want back. Change your request to include format and metadata fields: msgRequest.Fields = "messages(id,payload/headers)"; and msgRequest.Format = UsersResource.MessagesResource.ListRequest.FormatEnum.Metadata;. Now you can grab headers directly without making separate Get calls for each message. You’ll find the subject in the headers collection where name equals “Subject”. This beats fetching full message details one by one and won’t hit rate limits as hard.