Danny Hansen

When I was using the userfield to display to username of a selected user or group I wanted this field to display username and email adres. Si I create a custom control to display name and generate a mailto link:

using System;
using Microsoft.SharePoint.WebControls;
using Microsoft.SharePoint;
using System.Web.UI;

namespace Webcontrols
{
   public class EnhancedUserField : UserField
   {
      protected override void Render(System.Web.UI.HtmlTextWriter output)
      {
         if (this.ItemContext.FormContext.FormMode == SPControlMode.Display)
         {
            try
            {
               using (SPSite oSPSite = new SPSite(SPContext.Current.Site.Url))
               {
                  using (SPWeb oSPWeb = oSPSite.OpenWeb())
                  {
                     String usersString = base.ListItemFieldValue.ToString();
                     SPFieldUserValueCollection userValueColl = new SPFieldUserValueCollection(oSPWeb, usersString);

                     int count = 0;
                     foreach (SPFieldUserValue userValue in userValueColl)
                     {
                        count++;
                        SPUser siteUser = userValue.User;
                        System.Diagnostics.Trace.TraceInformation("User found: {0}", siteUser.Name);

                        if (!string.IsNullOrEmpty(siteUser.Email))
                        {
                           string email = string.Format("mailto:{0}", siteUser.Email);
                           output.WriteBeginTag("a");
                           output.WriteAttribute("HREF", email);
                           output.Write(HtmlTextWriter.TagRightChar);
                           output.WriteEncodedText(siteUser.Name);
                           output.WriteEndTag("a");
                           if(count > 1)
                              output.WriteEncodedText(" , ");
                        }
                        else
                        {
                           output.WriteEncodedText(siteUser.Name);
                        }
                     }
                  }
               }
            }
            catch { }
         }
         else
         {
            base.Render(output);
         }
      }
   }
}

U can use this in your page layout in this way:

<%@ Register Tagprefix="Webcontrols" Namespace="Webcontrols" Assembly="Webcontrols, Version=1.0.0.0, Culture=neutral, PublicKeyToken=868bd32625cae9fb" %>
Person: <WebControls:EnhancedUserField  FieldName="Person" runat="server"></WebControls:EnhancedUserField >