c# - How to show the current user using ASP MVC and EF -

developing asp .net mvc 3 application using c# , sql server 2005. using entity framework code first method.

i have interface log on (connection) related base have user table (contain login + password).

i want show current user logged. so, created viewmodel class user didn't result. tried in controller :

public actionresult logon()         {               var user = new userviewmodel();             user.nom_user = this.user.identity.name;             viewdata["userdetails"] = user;             return view();         } 

and add in master page :

    <% var user = viewdata["userdetails"] mvcapplication2.viewmodels.userviewmodel; %>  hello : <%: user.nom_user  %>! 

when execute, have error :

object reference not set instance of object.

you said placed code in masterpage. means run every view.

but have set viewdata["userdetails"] inside logon action. when navigate other action (such home/index action example) bomb because there's nothing inside viewdata["userdetails"] , of course user variable declared in masterpage null.

i recommend using child action that.

[childactiononly] public actionresult logedinuser() {     if (!request.isauthenticated)     {         return partialview();     }      var user = new userviewmodel();     user.nom_user = user.identity.name;     return partialview(user); } 

and in masterpage:

<% html.renderaction("logedinuser", "account"); %> 

or if prefer:

<%= html.action("logedinuser", "account") %> 

and have corresponding logedinuser.ascx partial typed view model:

<%@ control      language="c#"      inherits="system.web.mvc.viewusercontrol<userviewmodel>"  %>  <% if (model != null) { %>     <div>hello : <%= html.displayfor(x => x.nom_user) %></div> <% } %> 

phil haack blogged child actions in more details here.