title: How can I check if a string contains a special letter?
body: <p>I am building a program that gets a password as a string and checks its strength by a couple of factors. I want to check if the entered string contains a special character (like %,$,# etc.) but so far I couldn't able to figure it out. What is the best way to do so?</p>
  
  <p>Edit: I am not searching for a specific character. I need to search the string to find if it has some kind of a non-letter, non-digit character.</p>
  
  <p>Edit 2 : I want to do it without a loop.</p>