/// <summary>
/// Writes the specified value to the PDF stream.
/// </summary>
public void Write(PdfString value)
{
WriteSeparator(CharCat.Delimiter);
#if true
PdfStringEncoding encoding = (PdfStringEncoding)(value.Flags & PdfStringFlags.EncodingMask);
string pdf;
if ((value.Flags & PdfStringFlags.HexLiteral) == 0)
pdf = PdfEncoders.ToStringLiteral(value.Value, encoding, SecurityHandler);
else
pdf = PdfEncoders.ToHexStringLiteral(value.Value, encoding, SecurityHandler);
WriteRaw(pdf);
#else
switch (value.Flags & PdfStringFlags.EncodingMask)
{
case PdfStringFlags.Undefined:
case PdfStringFlags.PDFDocEncoding:
if ((value.Flags & PdfStringFlags.HexLiteral) == 0)
WriteRaw(PdfEncoders.DocEncode(value.Value, false));
else
WriteRaw(PdfEncoders.DocEncodeHex(value.Value, false));
break;
case PdfStringFlags.WinAnsiEncoding:
throw new NotImplementedException("Unexpected encoding: WinAnsiEncoding");
case PdfStringFlags.Unicode:
if ((value.Flags & PdfStringFlags.HexLiteral) == 0)
WriteRaw(PdfEncoders.DocEncode(value.Value, true));
else
WriteRaw(PdfEncoders.DocEncodeHex(value.Value, true));
break;
case PdfStringFlags.StandardEncoding:
case PdfStringFlags.MacRomanEncoding:
case PdfStringFlags.MacExpertEncoding:
default:
throw new NotImplementedException("Unexpected encoding");
}
#endif
this.lastCat = CharCat.Delimiter;
}
/// <summary>
/// Sets the entry to a direct string value.
/// </summary>
public void SetString(string key, string value)
{
this[key] = new PdfString(value);
}
/// <summary>
/// Prepares the security handler for encrypting the document.
/// </summary>
public void PrepareEncryption()
{
#if !SILVERLIGHT
Debug.Assert(this.document.securitySettings.DocumentSecurityLevel != PdfDocumentSecurityLevel.None);
int permissions = (int)this.Permission;
bool strongEncryption = this.document.securitySettings.DocumentSecurityLevel == PdfDocumentSecurityLevel.Encrypted128Bit;
PdfInteger vValue;
PdfInteger length;
PdfInteger rValue;
if (strongEncryption)
{
vValue = new PdfInteger(2);
length = new PdfInteger(128);
rValue = new PdfInteger(3);
}
else
{
vValue = new PdfInteger(1);
length = new PdfInteger(40);
rValue = new PdfInteger(2);
}
if (String.IsNullOrEmpty(this.userPassword))
this.userPassword = "";
// Use user password twice if no owner password provided.
if (String.IsNullOrEmpty(this.ownerPassword))
this.ownerPassword = this.userPassword;
// Correct permission bits
permissions |= (int)(strongEncryption ? (uint)0xfffff0c0 : (uint)0xffffffc0);
permissions &= unchecked((int)0xfffffffc);
PdfInteger pValue = new PdfInteger(permissions);
Debug.Assert(this.ownerPassword.Length > 0, "Empty owner password.");
byte[] userPad = PadPassword(this.userPassword);
byte[] ownerPad = PadPassword(this.ownerPassword);
this.md5.Initialize();
this.ownerKey = ComputeOwnerKey(userPad, ownerPad, strongEncryption);
byte[] documentID = PdfEncoders.RawEncoding.GetBytes(this.document.Internals.FirstDocumentID);
InitWidhUserPassword(documentID, this.userPassword, this.ownerKey, permissions, strongEncryption);
PdfString oValue = new PdfString(PdfEncoders.RawEncoding.GetString(this.ownerKey));
PdfString uValue = new PdfString(PdfEncoders.RawEncoding.GetString(this.userKey));
Elements[Keys.Filter] = new PdfName("/Standard");
Elements[Keys.V] = vValue;
Elements[Keys.Length] = length;
Elements[Keys.R] = rValue;
Elements[Keys.O] = oValue;
Elements[Keys.U] = uValue;
Elements[Keys.P] = pValue;
#endif
}
/// <summary>
/// Converts the specified value to String.
/// If the value not exists, the function returns the empty string.
/// </summary>
public string GetString(string key, bool create)
{
object obj = this[key];
if (obj == null)
{
if (create)
this[key] = new PdfString();
return "";
}
if (obj is PdfReference)
obj = ((PdfReference)obj).Value;
if (obj is PdfString)
return ((PdfString)obj).Value;
else if (obj is PdfStringObject)
return ((PdfStringObject)obj).Value;
else if (obj is PdfName)
return ((PdfName)obj).Value;
else if (obj is PdfNameObject)
return ((PdfNameObject)obj).Value;
throw new InvalidCastException("GetString: Object is not a string.");
}
/// <summary>
/// Encrypts a string.
/// </summary>
void EncryptString(PdfString value)
{
if (value.Length != 0)
{
byte[] bytes = value.EncryptionValue;
PrepareKey();
EncryptRC4(bytes);
value.EncryptionValue = bytes;
}
}
