ASP.NET Identity change password

Question

I need ability to change password for user by admin. So, admin should not enter a current password of user, he should have ability to set a new password. I look at ChangePas

Answer 1

For ASP.NET Core 3.1 users, this is a modernized iteration of the excellent answers provided by @Tseng and @BCA.

PasswordValidator is no longer a property on UserManager - instead, the property is an IList PasswordValidators. Furthermore, Identity now has a protected UpdatePasswordHash method that changes the password for you without needing to directly access the UserStore, which eliminates the need to manually hash and save the password anyway.

UserManager also has a public property, bool SupportsUserPassword, which replaces the need to test if Store implements IUserPasswordStore (internally, this is exactly what UserManager does in the SupportsUserPassword getter).

Since UpdatePasswordHash is protected, you do still need to extend the base UserManager. Its signature is:

protected Task UpdatePasswordHash(TUser user, string newPassword, bool validatePassword)

where validatePassword represents whether or not to run password validation. This does not default to true, unfortunately, so it needs to be supplied. The implementation looks like this:

public async Task ChangePasswordAsync(ApplicationUser user, string newPassword)
{
    if (!SupportsUserPassword)
    {
        return IdentityResult.Failed(new IdentityError
        {
            Description = "Current UserStore doesn't implement IUserPasswordStore"
        });
    }
            
    var result = await UpdatePasswordHash(user, newPassword, true);
    if (result.Succeeded)
        await UpdateAsync(user);

    return result;
}

As before, the first order of business is to ensure the current UserStore supports passwords.

Then, simply call UpdatePasswordHash with the ApplicationUser, the new password, and true to update that user's password with validation. If the update was successful, you still have to save the user so call UpdateAsync.