System.Text.Normalization.nativeNormalizationIsNormalizedString C# (CSharp) Method

        unsafe private static extern int nativeNormalizationIsNormalizedString(
            NormalizationForm NormForm, ref int iError,
            String lpString, int cwLength);

        internal static bool IsNormalized(string strInput, NormalizationForm normForm)
        {
            Normalization.EnsureInitialized(normForm);
            int num1 = 0;
            int num2 = (int)normForm;
            // ISSUE: explicit reference operation
            // ISSUE: variable of a reference type
            int&   iError   = @num1;
            string lpString = strInput;
            int    length   = lpString.Length;
            bool   flag     = Normalization.nativeNormalizationIsNormalizedString((NormalizationForm)num2, iError, lpString, length);

            if (num1 <= 8)
            {
                if (num1 == 0)
                {
                    return(flag);
                }
                if (num1 == 8)
                {
                    throw new OutOfMemoryException(Environment.GetResourceString("Arg_OutOfMemoryException"));
                }
            }
            else if (num1 == 87 || num1 == 1113)
            {
                throw new ArgumentException(Environment.GetResourceString("Argument_InvalidCharSequenceNoIndex"), "strInput");
            }
            throw new InvalidOperationException(Environment.GetResourceString("UnknownError_Num", (object)num1));
        }