HTML Helper syntax issue - html-helper

Question

I have this piece of code in a couple of cshtml pages:
#model bt2.Models.ScheduleWork
#using System.Security.Claims;
#{
bool Admin = User.IsInRole("Admin");
var identity = (ClaimsIdentity)User.Identity;
int Employee_ID = Int32.Parse(identity.FindFirst("DatabaseID").Value);
}
#using (Html.BeginForm())
{
#Html.AntiForgeryToken()
<div class="form-horizontal">
If I understand correctly, I should be able to turn this into a html helper. But I can't find the correct syntax.
I have created a cshtml called bthelper.cshtml and placed it in the App_Code folder
This was my first try:
#helper GetUserInfo() {
// Load user info into sever side variables for subsequent use
// Admin (true if an admin user)
// Employee_Id
#using System.Security.Claims;
#{
bool Admin = (User.IsInRole("Admin"));
var identity = (ClaimsIdentity)User.Identity;
int Employee_ID = Int32.Parse(identity.FindFirst("DatabaseID").Value);
}
}
Then my view cshtml became
#model bt2.Models.ScheduleWork
#bthelper.GetUserInfo()
#using (Html.BeginForm())
{
..........
....
When I run this I get
Unexpected "{" after "#" character. Once inside the body of a code block (#if {}, #{}, etc.) you do not need to use "#{" to switch to code.
With the highlight on the #{ line in the helper
So I tried all the permutations below, all with error messages
#helper GetUserInfo() {
#using System.Security.Claims;
bool Admin = (User.IsInRole("Admin"));
var identity = (ClaimsIdentity)User.Identity;
int Employee_ID = Int32.Parse(identity.FindFirst("DatabaseID").Value);
}
Unexpected "using" keyword after "#" character. Once inside code, you do not need to prefix constructs like "using" with "#".
Error on the #using line
#helper GetUserInfo() {
using System.Security.Claims;
bool Admin = (User.IsInRole("Admin"));
var identity = (ClaimsIdentity)User.Identity;
int Employee_ID = Int32.Parse(identity.FindFirst("DatabaseID").Value);
}
Namespace imports and type aliases cannot be placed within code blocks. They must immediately follow an "#" character in markup. It is recommended that you put them at the top of the page, as in the following example:
#using System.Drawing;
#{
// OK here to use types from System.Drawing in the page
}
Oh..... according to this my original syntax was actually correct
Can someone help me with the correct syntax? Razor syntax still confuses me. Contradictory error messages don't help