iTextSharp.text.pdf.qrcode.BitArray.IsRange C# (CSharp) Method

        public bool IsRange(int start, int end, bool value) {
            if (end < start) {
                throw new ArgumentException();
            }
            if (end == start) {
                return true; // empty range matches
            }
            end--; // will be easier to treat this as the last actually set bit -- inclusive    
            int firstInt = start >> 5;
            int lastInt = end >> 5;
            for (int i = firstInt; i <= lastInt; i++) {
                int firstBit = i > firstInt ? 0 : start & 0x1F;
                int lastBit = i < lastInt ? 31 : end & 0x1F;
                int mask;
                if (firstBit == 0 && lastBit == 31) {
                    mask = -1;
                }
                else {
                    mask = 0;
                    for (int j = firstBit; j <= lastBit; j++) {
                        mask |= 1 << j;
                    }
                }

                // Return false if we're looking for 1s and the masked bits[i] isn't all 1s (that is,
                // equals the mask, or we're looking for 0s and the masked portion is not all 0s
                if ((bits[i] & mask) != (value ? mask : 0)) {
                    return false;
                }
            }
            return true;
        }