List Contacts in ContactFolder

Question

I am trying to get a list of Contacts from a ContactFolder using Microsoft Graph API.

The code I am using is as follows:

GraphServiceClient graphClient = new GraphServiceClient (new CustomAuthentication ());
// build the request
var request = graphClient.Me.ContactFolders.Request();

// get all contact folders
var folders = await request.GetAsync();

// get the first folder
var folder = folders.FirstOrDefault();

//  get all contacts in that folder (Contacts is always null)
var contacts = folder.Contacts.ToList();

On the last line, the Contacts collection is null even though there are contacts in that folder when viewed through Outlook.

I tried to call folder.Contacts.GetAsync() however that method does not appear to be available:

Any help would be appreciated.

Answer 1

First you're requesting FirstOrDefault but this isn't a method exposed by IUserContactFoldersCollectionPage . You need to address the items within folders by index:

folders[0]
folders[1]
folders[etc]

You're also not populating the Contacts object. Keep in mind that Microsoft Graph is a REST API. It is provides a collection of stateless HTTP methods so it doesn't automatically hydrate your object model. You need to specifically request the data for Contacts :

.Contacts.Request().GetAsync();

Also note that ContactFolders will only return results if there are multiple folders. The default Contacts folder is never returned. If a user has no additional folders, this will return an empty result.

With this in mind, you would retrieve the Contacts like this:

GraphServiceClient graphClient = new GraphServiceClient(new CustomAuthentication());

// get all contact folders
var folders = await graphClient
    .Me
    .ContactFolders
    .Request()
    .GetAsync();

if (folders.Count > 0)
{
    // Get contacts from that first folder
    var folderContacts = await graphClient
        .Me
        .ContactFolders[folders[0].Id]
        .Contacts
        .Request()
        .GetAsync();
}
else
{
    // This user only has the default contacts folder
    var defaultContacts = await graphClient
        .Me
        .Contacts
        .Request()
        .GetAsync();
}