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Rajesh Lohar's avatar
Rajesh Lohar
Copper Contributor
Jul 16, 2020

Authenticate a user in MS teams custom app using asp.net and c#

Hi,

I am working on a custom app for MS teams. It is not a bot but it is a tab app.  I need to authenticate logged in user to MS teams using c#. Please let me know how to authenticate user and show the user profile of logged in user.

 

Thanks,

 

6 Replies

  • gk_vasudev's avatar
    gk_vasudev
    Brass Contributor

    Hi Rajesh Lohar 

     

     

    Use REST API service provided by Microsoft inside your application.

    you can authenticate the user and and fetch user details using API.

     

    Any services , be it Tabs, Bots etc., everything uses the same authentication process.

     

    You can use the following links to get more idea of how to do it.

    https://www.c-sharpcorner.com/article/authentication-with-office-365-in-C-Sharp/

    https://github.com/microsoftgraph/aspnet-snippets-sample

     

    cheers.

    • Rajesh Lohar's avatar
      Rajesh Lohar
      Copper Contributor

      Hi gk_vasudev ,

      Thank you so much for your reply. 

      Is it possible that user is logged in to MS teams already so it can auto login to custom app pages using same credentials?

      As per your answer, user has to login by his Office 365 credentials again in the app.

       

      Thanks,

       

       

      • gk_vasudev's avatar
        gk_vasudev
        Brass Contributor

        Rajesh Lohar
        if thats the case ,
        Then u could a request an authentication token from microsoft teams
        and use the token information to authenticate the user to your application.
        by this way the user would be automatically logs in to your custom application.

        This is "Single Sign-on" Concept based on the "on-behalf-of" flow.

        Please go through these links to get a clear idea about the process and how to do it.
        its mostly in Js, but i think you would be able to figure out to do it in asp.net and c#

        https://docs.microsoft.com/en-us/microsoftteams/platform/tabs/how-to/authentication/auth-aad-sso

        https://docs.microsoft.com/en-us/azure/active-directory/develop/v2-oauth2-on-behalf-of-flow#service-to-service-access-token-request

        https://docs.microsoft.com/en-us/azure/active-directory/develop/active-directory-v2-protocols

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