iTextSharp.text.pdf.AcroFields.RenameField C# (CSharp) Метод

        public bool RenameField(String oldName, String newName) {
            int idx1 = oldName.LastIndexOf('.') + 1;
            int idx2 = newName.LastIndexOf('.') + 1;
            if (idx1 != idx2)
                return false;
            if (!oldName.Substring(0, idx1).Equals(newName.Substring(0, idx2)))
                return false;
            if (fields.ContainsKey(newName))
                return false;
            Item item = (Item)fields[oldName];
            if (item == null)
                return false;
            newName = newName.Substring(idx2);
            PdfString ss = new PdfString(newName, PdfObject.TEXT_UNICODE);
            item.WriteToAll( PdfName.T, ss, Item.WRITE_VALUE | Item.WRITE_MERGED);
            item.MarkUsed( this, Item.WRITE_VALUE );
            fields.Remove(oldName);
            fields[newName] = item;
            return true;
        }