C# ByteBuffer.WriteTo方法代码示例

 /**
  * Signs a PDF where space was already reserved.
  * @param reader the original PDF
  * @param fieldName the field to sign. It must be the last field
  * @param outs the output PDF
  * @param externalSignatureContainer the signature container doing the actual signing. Only the 
  * method ExternalSignatureContainer.sign is used
  * @throws DocumentException
  * @throws IOException
  * @throws GeneralSecurityException 
  */
 public static void SignDeferred(PdfReader reader, String fieldName, Stream outs, IExternalSignatureContainer externalSignatureContainer) {
     AcroFields af = reader.AcroFields;
     PdfDictionary v = af.GetSignatureDictionary(fieldName);
     if (v == null)
         throw new DocumentException("No field");
     if (!af.SignatureCoversWholeDocument(fieldName))
         throw new DocumentException("Not the last signature");
     PdfArray b = v.GetAsArray(PdfName.BYTERANGE);
     long[] gaps = b.AsLongArray();
     if (b.Size != 4 || gaps[0] != 0)
         throw new DocumentException("Single exclusion space supported");
     IRandomAccessSource readerSource = reader.SafeFile.CreateSourceView();
     Stream rg = new RASInputStream(new RandomAccessSourceFactory().CreateRanged(readerSource, gaps));
     byte[] signedContent = externalSignatureContainer.Sign(rg);
     int spaceAvailable = (int)(gaps[2] - gaps[1]) - 2;
     if ((spaceAvailable & 1) != 0)
         throw new DocumentException("Gap is not a multiple of 2");
     spaceAvailable /= 2;
     if (spaceAvailable < signedContent.Length)
         throw new DocumentException("Not enough space");
     StreamUtil.CopyBytes(readerSource, 0, gaps[1] + 1, outs);
     ByteBuffer bb = new ByteBuffer(spaceAvailable * 2);
     foreach (byte bi in signedContent) {
         bb.AppendHex(bi);
     }
     int remain = (spaceAvailable - signedContent.Length) * 2;
     for (int k = 0; k < remain; ++k) {
         bb.Append((byte)48);
     }
     bb.WriteTo(outs);
     StreamUtil.CopyBytes(readerSource, gaps[2] - 1, gaps[3] + 1, outs);
 }

//.........这里部分代码省略.........
         if (structElem == null)
             return;
         PdfDictionary dict =  item.GetObjAsDict();
         if (dict == null || !dict.CheckType(PdfName.ANNOT))
             return;
         PdfDictionary ap = dict.GetAsDict(PdfName.AP);
         if (ap == null)
             return;
         PdfNumber structParent = dict.GetAsNumber(PdfName.STRUCTPARENT);
         if (structParent == null)
             return;
         PdfStream stream = ap.GetAsStream(PdfName.N);
         if (stream == null)
             return;
         stream.Put(PdfName.STRUCTPARENT, structParent);
         PdfIndirectReference xobjr = ap.GetAsIndirectObject(PdfName.N);
         if (xobjr == null)
             return;
         // remove the annotation from the page
 	    for (int i = 0; i < annots.Length; i++) {
 		    PdfIndirectReference annotref = annots.GetAsIndirectObject(i);
 		    if (item.GetObjRef().Number == annotref.Number) {
 			    annots.Remove(i);
 			    break;
 		    }
 	    }
 	    // replace the existing attributes by a PrintField attribute
         PdfDictionary attribute = new PdfDictionary();
         attribute.Put(PdfName.O, PdfName.PRINTFIELD);
         PdfString description = dict.GetAsString(PdfName.TU);
         if (description == null)
             description = dict.GetAsString(PdfName.T);
         if (PdfName.BTN.Equals(dict.Get(PdfName.FT))) {
             PdfNumber fflags = dict.GetAsNumber(PdfName.FF);
             if (fflags != null) {
                 int ff = fflags.IntValue;
                 if ((ff & PdfFormField.FF_PUSHBUTTON) != 0)
                     attribute.Put(PdfName.ROLE, PdfName.PB);
                 // I don't think the condition below will ever be true
                 if ((ff & PdfFormField.FF_RADIO) != 0)
                     attribute.Put(PdfName.ROLE, PdfName.rb);
                 else
                     attribute.Put(PdfName.ROLE, PdfName.CB);
             }
         }
         else {
             attribute.Put(PdfName.ROLE, PdfName.TV);
         }
         attribute.Put(PdfName.DESC, description);
         // Updating the values of the StructElem dictionary
         PdfString t = structElem.GetAsString(PdfName.T);
         if (t == null || t.ToString().Trim().Length == 0)
             structElem.Put(PdfName.T, dict.GetAsString(PdfName.T));
         structElem.Put(PdfName.A, attribute);
         structElem.Put(PdfName.S, PdfName.P);
         structElem.Put(PdfName.PG, pageref);
       	// Defining a new MCID
        	int mcid = items.ProcessMCID(structParents, item.GetRef());
         LOGGER.Info("Using MCID " + mcid);
         structElem.Put(PdfName.K, new PdfNumber(mcid));
         // removing the annotation from the parent tree
         items.RemoveFromParentTree(structParent);
         // Adding the XObject to the page
         PdfName xobj = new PdfName("XObj" + structParent.IntValue);
         LOGGER.Info("Creating XObject with name " + xobj);
         xobjects.Put(xobj, xobjr);
         PdfArray array = dict.GetAsArray(PdfName.RECT);
         // Getting the position of the annotation
         Rectangle rect = new Rectangle(
             array.GetAsNumber(0).FloatValue, array.GetAsNumber(1).FloatValue,
             array.GetAsNumber(2).FloatValue, array.GetAsNumber(3).FloatValue);
         rect.Normalize();
         // A Do operator is forbidden inside a text block
         if (inText && !btWrite) {
             LOGGER.Debug("Introducing extra ET");
             byte[] bytes = Encoding.ASCII.GetBytes("ET\n");
             baos.Write(bytes, 0, bytes.Length);
             etExtra = true;
         }
 	    // Writing the marked-content sequence with the Do operator
 	    // Note that the position assumes that the CTM wasn't changed in the graphics state
 	    // TODO: do the math if the CTM did change!
         ByteBuffer buf = new ByteBuffer();
         buf.Append("/P <</MCID ");
         buf.Append(mcid);
         buf.Append(">> BDC\n");
         buf.Append("q 1 0 0 1 ");
         buf.Append(rect.Left.ToString(CultureInfo.InvariantCulture));
         buf.Append(" ");
         buf.Append(rect.Bottom.ToString(CultureInfo.InvariantCulture));
         buf.Append(" cm ");
         buf.Append(xobj.GetBytes());
         buf.Append(" Do Q\n");
         buf.Append("EMC\n");
         buf.Flush();
         buf.WriteTo(baos);
 	    // if we were inside a text block, we've introduced an ET, so we'll need to write a BT
         if (inText)
             btWrite = true;
     }