I using Windows Azure Active Directory login for my MVC 5 application. Can somebody give me idea how I can check if username already exist in Windows Azure Active Directory?
What is general approach to do this?
There is Azure AD Graph API which can be used with helper classes (see code.msdn.microsoft.com/windowsazure/) or via HttpClient
Example of query to get user: https://graph.windows.net/contoso.com/users/{0}@contoso.com?api-version=2013-04-05
where {0} is your name
More queries: http://msdn.microsoft.com/en-us/library/azure/jj126255.aspx
Detailed demo: http://msdn.microsoft.com/en-us/library/azure/dn151791.aspx
