Infopath's built in Username() function returning “i:0#.w|Domain\UserName” instead of just UserName

 I can modify the UserName() return string to display only the username as opposed to "i:0#.w|Domain\UserName"
 using substring-after function we can get only user name instead of "i:0#.w|Domain\UserName"

Eg:


Here I will use two controls one is "LoginUserFullName" ans second is "UserName"
 "LoginUserFullName" control has "i:0#.w|Domain\UserName" now am going to store the user name with out domain in "UserName"control by using substring-after(LoginUserFullName, "\")