// JavaScript Document

function trim(stringa)
{ 
  while (stringa.substring(0,1) == ' ')
  {
      stringa = stringa.substring(1, stringa.length);
  }
  while (stringa.substring(stringa.length-1, stringa.length) == ' ')
  {
      stringa = stringa.substring(0,stringa.length-1);
  }
  return stringa;
}


function is_valid_mail(stringa)
{
  // [a-zA-Z0-9_\.]+@[a-zA-Z0-9-]+\.[a-zA-Z]{0,4}
  var filter_email = /^\w+([\.-]?\w+)*@\w+([\.-]?\w+)*\.(\w{2}|(com|net|org|edu|it|mil|gov|arpa|biz|aero|name|coop|info|pro|museum))$/;    
  
  if ( !filter_email.test(stringa) ) return false;
  else return true;
}

function is_alphanum_signal(str)
{ 
  var toTest = new RegExp("^[A-Za-z0-9\._]+$");
  if (!(toTest.test(str)))
  {
    return false;
  }
  else
  {
    return true;
  }
}

function is_mail_address2(email)
{
  email = trim(email);  
  var toTest = new RegExp("^[A-Za-z0-9._%+-]+@[A-Za-z0-9.-]+\.[A-Za-z]{2,4}$");
   
  if (!(toTest.test(email)))
  {
    return false;
  }
  else
  {
    return true;
  }
}

function is_valid_tel_number(str)
{ 
  var toTest = new RegExp("^[0-9 \.-]*$");
  if (!(toTest.test(str)))
  {
    return false;
  }
  else
  {
    return true;
  }
}

function is_valid_date(str)
{
  var toTest = new RegExp(/^\d{1,2}(\-|\/|\.)\d{1,2}\1\d{4}$/);
  if (!(toTest.test(str)))
  {
    return false;
  }
  else
  {
    return true;
  }
}