internal static bool IsLowSurrogate(int ch)
 {
     return(XmlCharType.InRange(ch, 56320, 57343));
 }
 internal static bool IsSurrogate(int ch)
 {
     return(XmlCharType.InRange(ch, 55296, 57343));
 }
 internal static bool IsHighSurrogate(int ch)
 {
     return(XmlCharType.InRange(ch, 55296, 56319));
 }