//--------------------------------------------------------------------------------------------------
function isEmail(string) {
	if (string.search(/^\w+((-\w+)|(\.\w+))*\@[A-Za-z0-9]+((\.|-)[A-Za-z0-9]+)*\.[A-Za-z0-9]+$/) != -1)
        	return true;
	else
        	return false;
}

//--------------------------------------------------------------------------------------------------
function checkEmpty(field, name) {
	var valid = (field.value) || (field.value!="");
        if (!valid) {
        	alert("Please enter a " + name + ".");
        	field.focus();
        }
       	return valid;
}

//--------------------------------------------------------------------------------------------------
function isNumber(inputStr) {
 for (var i = 0; i < inputStr.length; i++) {
  var oneChar = inputStr.substring(i, i + 1)
  if (oneChar < "0" || oneChar > "9") {
   return false
  }
 } 
 return true;
}

//--------------------------------------------------------------------------------------------------
function isFloatNumber(sText)
{
  var ValidChars = "0123456789.";
  var IsNumber = true;
  var Char;
  var i, j, count = 0;

  Char = sText.charAt(0)
  if (Char == "-") { j = 1; }
  else { j = 0; }

  for (i = j; i < sText.length && IsNumber == true; i++){ 
    Char = sText.charAt(i);
    if (Char == '.') { count = count + 1; }
    if (ValidChars.indexOf(Char) == -1 || count > 1) { IsNumber = false; }
  }
  return IsNumber;
}

//--------------------------------------------------------------------------------------------------
function checkCardNumber(aType, aNum, aCVV2) {
	var dig="0";
	var t=0;

	if(aType[0].checked) { t=1; }
	else { 	
		if(aType[1].checked) { t=2; }
		else { 
			if(aType[2].checked) { t=3; }; 
		};
	}
	switch(t) {
	 case 1:
		dig="4";
		break;
	 case 2:
		dig="5";
		break;
	 case 3:
		dig="6";
		break;
	 default:
		return (true);
	}
	if (dig!=aNum.charAt(0)) {
		alert("Error! Wrong card type or card number!");
		return (false);
	}
	if( aCVV2.length!=3 ){
		alert("Error! Wrong CVV2!");
		return false;
	}
	return (true);
}