title: How to perform validation on textfield for phone number entered by user in iPhone?
body: <p>I have an application where I have I a textfield where user enters his mobile number including his country code. The format of the mobile number to be entered is +91-9884715715. When the user enters his/her mobile number initially validation should be performed that the first value entered by user is '+' and then the number that is entered after + should not be less that 0.</p>
  
  <p>But after this I am getting confused that how to get the number of numbers entered between + and -, because user enters the country code and the length of numbers entered between + and - must be dynamic not static.</p>