Someone

if (event.keyCode == 13)
{
	var pattern:RegExp = /\r|\n/g;
	var formattedText:String = myTextArea.text.replace(pattern,"");
	var tmpNum:Number = Number(formattedText);
	
	if (typeof(tmpNum) == "number" && tmpNum <= maximumValue && tmpNum >= minimumValue)
	{
		updateStepper(tmpNum);
		lastValueStr = formattedText;
	}
	else
	{
		updateStepper(Number(lastValueStr));
	}
}