.NET API Catalog

net481
    namespace Microsoft.AspNet.Identity
{
    public class UserManager<TUser> : IDisposable
        where TUser, class
    {
        [AsyncStateMachine(typeof(<GetUserIdAsync>d__73))]
        public virtual Task<string> GetUserIdAsync(TUser user);
    }
}

Information specific to `net481`
.NET Framework	4.5.14.5.24.64.6.14.6.24.74.7.14.7.24.84.8.1
Assembly	Microsoft.AspNet.Identity , Version=3.0.0.0, PublicKeyToken=adb9793829ddae60
Referencing	Your project needs a package reference to `Microsoft.AspNet.Identity`.
Package	Microsoft.AspNet.Identity net451
Preview	This API is contained in a prerelease package.
Platform Restrictions	This framework does not have platform annotations.

Built-in API
Package-provided API