The specified user could not be found through web ensure user

Question

Hi,
If user  doesn't exists in the active directory,blank value/message needs to be displayed.
For this i am writing the code as below,but if user is not found i am planning to display the else part.
But problem here is,it is bombing up if user is not found and displaying the exception.
Please let me know to handle the same. 
using (SPSite site = new SPSite("http://servername:port/sites/site1"))
using (SPWeb web = site.OpenWeb())
SPUser user = web.EnsureUser("userid");
                    if (user != null)
                        Console.WriteLine(user.Name.ToString());
                    else
                        Console.WriteLine("User Not Found");
Thanks & Regards, Sudheer

Answer 1

wrap in try/catch block.
if you notice, the documentation for EnsureUser (https://msdn.microsoft.com/en-us/library/microsoft.sharepoint.spweb.ensureuser.aspx) is very clear:
Parameters
logonName
Type: System.String
The logon name (Domain\User_Alias) of the user.
Return value
Type: Microsoft.SharePoint.SPUser
A user with the specified logon name.
Exceptions
Exception
Condition
SPException
The user with the specified logonName cannot be found in Active Directory.
Scott Brickey
MCTS, MCPD, MCITP
www.sbrickey.com
Strategic Data Systems - for all your SharePoint needs