function Form_Validator(theForm)
{

var digits = "0123456789";
var phoneNumberDelimiters = "()- ";
var validWorldPhoneChars = phoneNumberDelimiters + "+";
var minDigitsInIPhoneNumber = 10;

function isInteger(s)
{   var i;
    for (i = 0; i < s.length; i++)
    {   
        // Check that current character is number.
        var c = s.charAt(i);
       if (((c < "0") || (c > "9"))) return(false);
    }
    // All characters are numbers.
    return(true);
}

function stripCharsInBag(s, bag)
{   var i;
    var returnString = "";
    // Search through string's characters one by one.
    // If character is not in bag, append to returnString.
    for (i = 0; i < s.length; i++)
    {   
        // Check that current character isn't whitespace.
        var c = s.charAt(i);
        if (bag.indexOf(c) == -1) returnString += c;
    }
    return(returnString);
}

function checkInternationalPhone(strPhone){
s=stripCharsInBag(strPhone,validWorldPhoneChars);
return(isInteger(s) && s.length >= minDigitsInIPhoneNumber);
}

  if (theForm.name.value == "")
  {
     alert("Please enter your Name.");
     theForm.name.focus();
     return(false);
  }
  else if (theForm.phone.value == "")
  {
     alert("Please enter your Telephone Number");
     theForm.phone.focus();
     return(false);
  }
var PhoneNo = theForm.phone;
if (checkInternationalPhone(PhoneNo.value)==false)
{
 alert("Please enter valid telephone number");
 theForm.phone.focus();
 return(false);
}
   if (theForm.time.value == "")
  {
     alert("Please enter your Best Time to call");
     theForm.time.focus();
     return(false);
  }
   if (theForm.address.value == "")
  {
     alert("Please enter your Address");
     theForm.address.focus();
     return(false);
  }

   return(true);
}