老版本PHP转义Json里的特殊字符的函数

# list from .json.: (\b backspace, \f formfeed)
public function escapeJsonString($value) {
  $escapers = array("\\", "/", "\"", "\n", "\r", "\t", "\x08", "\x0c");
  $replacements = array("\\\\", "\\/", "\\\"", "\\n", "\\r", "\\t", "\\f", "\\b");
  $result = str_replace($escapers, $replacements, $value);
  return $result;
}