title: how to split the word and get the 4 letter prefix in C#
body: <p>i have a username= LICTowner.</p>
  
  <p>i need to get the prefix from the word LICTowner i.e LICT.</p>
  
  <p>how to split the word and get the 4 letter prefix.</p>
  
  <p>in asp.net using C#</p>