internal static int CompareOrdinalIgnoreCaseEx(string strA, int indexA, string strB, int indexB, int lengthA, int lengthB)
 {
     return(TextInfo.InternalCompareStringOrdinalIgnoreCase(strA, indexA, strB, indexB, lengthA, lengthB));
 }
 internal static int CompareOrdinalIgnoreCase(string str1, string str2)
 {
     return(TextInfo.InternalCompareStringOrdinalIgnoreCase(str1, 0, str2, 0, str1.Length, str2.Length));
 }