function textFieldCheck(mandatory) {
    check=false;
    message='';
        
    for (i in mandatory) {
        if (document.getElementById(i).value=='') {
            message=message+mandatory[i]+', ';
            //alert ('One or more mandatory fields have not been completed. Please correct this to continue.');
            check=false;
            //break;
        }
        else {
            check=true;
        }
    }
    if (message!='') {
        message='The following required fields have not been completed: \n\n'+message;
        message_object=new String(message);
        message=message_object.substr(0,message_object.length-2);
        alert(message);
        check=false;
    }
    return check;
}

function textCounter( field, countfield, maxlimit ) {
  if ( field.value.length > maxlimit )
  {
    field.value = field.value.substring( 0, maxlimit );
    return false;
  }
  else
  {
    countfield.value = maxlimit - field.value.length;
  }
}

function emailCheck (emailStr) {
    var emailPat=/^(.+)@(.+)$/
    //var specialChars="\\(\\)<>@,;:\\\\\\\"\\.\\[\\]\\/\\?\\!\\£\\$\\%\\&\\#\\~\\*\\'\\|\\`\\=\\¬\\¦\\}\\{\\+\\^"
    //var validChars="\[\\s" + specialChars + "\]"
    var validChars="[a-zA-Z0-9_-]"
    var quotedUser="(\"[^\"]*\")"
    var ipDomainPat=/^\[(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})\]$/
    var atom=validChars + '+'
    var word="(" + atom + "|" + quotedUser + ")"
    var userPat=new RegExp("^" + word + "(\\." + word + ")*$")
    var domainPat=new RegExp("^" + atom + "(\\." + atom +")*$")
    var matchArray=emailStr.match(emailPat)
    if (matchArray==null) {
        alert("Email address seems incorrect (check @ and .'s)")
        return false
    }
    var user=matchArray[1]
    var domain=matchArray[2]

    if (user.match(userPat)==null) {
            alert("Email address doesn't seem to be valid.")
            return false
    }

    var IPArray=domain.match(ipDomainPat)
    if (IPArray!=null) {
      for (var i=1;i<=4;i++) {
        if (IPArray[i]>255) {
            alert("Email address has an invalid destination IP.")
        return false
        }
        }
     return true
    }
    var domainArray=domain.match(domainPat)
    if (domainArray==null) {
        alert("Email address has an invalid domain name")
        return false
    }

    var atomPat=new RegExp(atom,"g")
    var domArr=domain.match(atomPat)
    var len=domArr.length
    if (domArr[domArr.length-1].length<2 || 
            domArr[domArr.length-1].length>4) {
        alert("Email address must end in a three-letter or four-letter domain, or two letter country.")
        return false
    }
    if (len<2) {
         var errStr="Email address doesn't have a hostname." ;
         alert(errStr);
        return false;
        }
    return true;
}