title: ASP.NET membership & .net Core
body: <p>My database was built with <code>SqlMembershipProvider</code> as described <a href="https://www.asp.net/web-forms/overview/older-versions-security/membership/creating-the-membership-schema-in-sql-server-cs" rel="nofollow noreferrer">here</a>.</p>
  
  <p>I am using <code>System.Web.Security;</code> </p>
  
  <p>To check if user exists I am using: <code>Membership.ValidateUser(u.UserName, u.Password);</code></p>
  
  <p>I would like to move to <code>.net core</code> and <code>System.Web.Security;</code> is not supported - 
  so instead of <code>Membership.ValidateUser(u.UserName, u.Password);</code> I was thinking to query the db and check if the user exists,  but the passwords in the db are hashed. </p>
  
  <p>How can I check if user is exists? 
  Can I decrypt the passwords stored in the db? 
  What are my options?</p>
  
  <p>Thanks.</p>