function checkNumber(sText) {
  return (/^\d+$/.test(sText));
}
   
function checkPrice(sText) {
  return (/^\d+(\.\d{1,2})?$/.test(sText));
}

function checkEmail(sText) {  
  return (/^[A-z0-9]{1}[A-z0-9\._-]+@[A-z0-9\.-]+\.[A-z]{2,4}$/.test(sText));    
}

function checkImageFileExtension(sText) {
  //return (/^[a-zA-Z0-9-_\.]+\.(jpg|gif|png)$/.test(sText));
  return true;
}

function checkPhoneNumber(sText) {
  //return (/^[2-9]\d{2}-\d{3}-\d{4}$/.test(sText));
  return true;
}