Table of Contents

Class PdfObject

Namespace
iText.Kernel.Pdf
Assembly
itext.kernel.dll
public abstract class PdfObject
Inheritance
PdfObject
Derived
Inherited Members

Constructors

PdfObject() 

protected PdfObject()

Fields

ARRAY 

public const byte ARRAY = 1

Field Value

byte

BOOLEAN 

public const byte BOOLEAN = 2

Field Value

byte

DICTIONARY 

public const byte DICTIONARY = 3

Field Value

byte

FLUSHED

Indicates if the object has been flushed.

protected const short FLUSHED = 1

Field Value

short

FORBID_RELEASE

Indicates that the object is highly sensitive and we do not want to release it even if release() is called.

protected const short FORBID_RELEASE = 128

Field Value

short

Remarks

Indicates that the object is highly sensitive and we do not want to release it even if release() is called. This flag can be set in stamping mode in object wrapper constructors and is automatically set when setModified flag is set (we do not want to release changed objects). The flag is set automatically for some wrappers that need document even in reader mode (FormFields etc).

FREE

Indicates that the indirect reference of the object could be reused or have to be marked as free.

protected const short FREE = 2

Field Value

short

INDIRECT_REFERENCE 

public const byte INDIRECT_REFERENCE = 5

Field Value

byte

LITERAL 

public const byte LITERAL = 4

Field Value

byte

MODIFIED

Indicates that object changed (is used in append mode).

protected const short MODIFIED = 8

Field Value

short

MUST_BE_FLUSHED

For internal usage only.

protected const short MUST_BE_FLUSHED = 32

Field Value

short

Remarks

For internal usage only. Marks objects that shall be written to the output document. Option is needed to build the correct PDF objects tree when closing the document. As a result it avoids writing unused (removed) objects.

MUST_BE_INDIRECT

Indicates that the object shall be indirect when it is written to the document.

protected const short MUST_BE_INDIRECT = 64

Field Value

short

Remarks

Indicates that the object shall be indirect when it is written to the document. It is used to postpone the creation of indirect reference for the objects that shall be indirect, so it is possible to create such objects without PdfDocument instance.

NAME 

public const byte NAME = 6

Field Value

byte

NULL 

public const byte NULL = 7

Field Value

byte

NUMBER 

public const byte NUMBER = 8

Field Value

byte

ORIGINAL_OBJECT_STREAM

Indicates that the indirect reference of the object represents ObjectStream from original document.

protected const short ORIGINAL_OBJECT_STREAM = 16

Field Value

short

Remarks

Indicates that the indirect reference of the object represents ObjectStream from original document. When PdfReader read ObjectStream reference marked as OriginalObjectStream to avoid further reusing.

READING

Indicates that definition of the indirect reference of the object still not found (e.g. keys in XRefStm).

protected const short READING = 4

Field Value

short

READ_ONLY

Indicates that we do not want this object to be ever written into the resultant document (because of multiple objects read from the same reference inconsistency).

protected const short READ_ONLY = 256

Field Value

short

STREAM 

public const byte STREAM = 9

Field Value

byte

STRING 

public const byte STRING = 10

Field Value

byte

UNENCRYPTED

Indicates that this object is not encrypted in the encrypted document.

protected const short UNENCRYPTED = 512

Field Value

short

Remarks

Indicates that this object is not encrypted in the encrypted document. E.g. digital signature dictionary /Contents entry shall not be encrypted.

indirectReference

If object is flushed the indirect reference is kept here.

protected PdfIndirectReference indirectReference

Field Value

PdfIndirectReference

Methods

CheckState(short)

Checks state of the flag of current object.

protected virtual bool CheckState(short state)

Parameters

state short

special flag to check

Returns

bool

true if the state was set.

ClearState(short)

Clear state of the flag of current object.

protected virtual PdfObject ClearState(short state)

Parameters

state short

special flag state to clear

Returns

PdfObject

this PdfObject

Clone()

Creates clone of the object which belongs to the same document as original object.

public virtual PdfObject Clone()

Returns

PdfObject

cloned object.

Remarks

Creates clone of the object which belongs to the same document as original object. New object shall not be used in other documents.

Clone(ICopyFilter)

Creates clone of the object which belongs to the same document as original object.

public virtual PdfObject Clone(ICopyFilter filter)

Parameters

filter ICopyFilter

Filter what will be copied or not

Returns

PdfObject

cloned object.

Remarks

Creates clone of the object which belongs to the same document as original object. New object shall not be used in other documents.

CopyContent(PdfObject, PdfDocument)

Copies object content from object 'from'.

protected virtual void CopyContent(PdfObject from, PdfDocument document)

Parameters

from PdfObject

object to copy content from.

document PdfDocument

document to copy object to.

CopyContent(PdfObject, PdfDocument, ICopyFilter)

Copies object content from object 'from'.

protected virtual void CopyContent(PdfObject from, PdfDocument document, ICopyFilter filter)

Parameters

from PdfObject

object to copy content from.

document PdfDocument

document to copy object to.

filter ICopyFilter

ICopyFilter a filter that will apply on dictionaries and array Use NullCopyFilter for no filtering

CopyTo(PdfDocument)

Copies object to a specified document.

public virtual PdfObject CopyTo(PdfDocument document)

Parameters

document PdfDocument

document to copy object to.

Returns

PdfObject

copied object.

Remarks

Copies object to a specified document.

NOTE: Works only for objects that are read from document opened in reading mode, otherwise an exception is thrown.

CopyTo(PdfDocument, bool)

Copies object to a specified document.

public virtual PdfObject CopyTo(PdfDocument document, bool allowDuplicating)

Parameters

document PdfDocument

document to copy object to.

allowDuplicating bool

indicates if to allow copy objects which already have been copied. If object is associated with any indirect reference and allowDuplicating is false then already existing reference will be returned instead of copying object. If allowDuplicating is true then object will be copied and new indirect reference will be assigned.

Returns

PdfObject

copied object.

Remarks

Copies object to a specified document.

NOTE: Works only for objects that are read from document opened in reading mode, otherwise an exception is thrown.

CopyTo(PdfDocument, bool, ICopyFilter)

Copies object to a specified document.

public virtual PdfObject CopyTo(PdfDocument document, bool allowDuplicating, ICopyFilter copyFilter)

Parameters

document PdfDocument

document to copy object to.

allowDuplicating bool

indicates if to allow copy objects which already have been copied. If object is associated with any indirect reference and allowDuplicating is false then already existing reference will be returned instead of copying object. If allowDuplicating is true then object will be copied and new indirect reference will be assigned.

copyFilter ICopyFilter

ICopyFilter a filter to apply while copying arrays and dictionaries Use NullCopyFilter for no filtering

Returns

PdfObject

copied object.

Remarks

Copies object to a specified document.

NOTE: Works only for objects that are read from document opened in reading mode, otherwise an exception is thrown.

CopyTo(PdfDocument, ICopyFilter)

Copies object to a specified document.

public virtual PdfObject CopyTo(PdfDocument document, ICopyFilter copyFilter)

Parameters

document PdfDocument

document to copy object to.

copyFilter ICopyFilter

ICopyFilter a filter to apply while copying arrays and dictionaries Use NullCopyFilter for no filtering

Returns

PdfObject

copied object.

Remarks

Copies object to a specified document.

NOTE: Works only for objects that are read from document opened in reading mode, otherwise an exception is thrown.

Flush()

Flushes the object to the document.

public void Flush()

Flush(bool)

Flushes the object to the document.

public void Flush(bool canBeInObjStm)

Parameters

canBeInObjStm bool

indicates whether object can be placed into object stream.

GetIndirectReference()

Gets the indirect reference associated with the object.

public virtual PdfIndirectReference GetIndirectReference()

Returns

PdfIndirectReference

indirect reference.

Remarks

Gets the indirect reference associated with the object. The indirect reference is used when flushing object to the document.

GetObjectType()

Gets object type.

public abstract byte GetObjectType()

Returns

byte

object type.

IsArray()

Checks if this PdfObject is of the type PdfArray.

public virtual bool IsArray()

Returns

bool

true or false

IsBoolean()

Checks if this PdfObject is of the type PdfBoolean.

public virtual bool IsBoolean()

Returns

bool

true or false

IsDictionary()

Checks if this PdfObject is of the type PdfDictionary.

public virtual bool IsDictionary()

Returns

bool

true or false

IsFlushed()

Indicates is the object has been flushed or not.

public virtual bool IsFlushed()

Returns

bool

true if object has been flushed, otherwise false.

IsIndirect()

Checks if object is indirect.

public virtual bool IsIndirect()

Returns

bool

returns true if object is indirect or is to be indirect in the resultant document.

Remarks

Checks if object is indirect.
Note: Return value true doesn't necessarily mean that indirect reference of this object is not null at the moment. Object could be marked as indirect and be transformed to indirect on flushing.
E.g. all PdfStreams are transformed to indirect objects when they are written, but they don't always have indirect references at any given moment.

IsIndirectReference()

Checks if this PdfObject is of the type PdfIndirectReference.

public virtual bool IsIndirectReference()

Returns

bool

true if this is an indirect reference, otherwise false

IsLiteral()

Checks if this PdfObject is of the type PdfLiteral.

public virtual bool IsLiteral()

Returns

bool

true if this is a literal, otherwise false

IsModified()

Indicates is the object has been set as modified or not.

public virtual bool IsModified()

Returns

bool

true is object has been set as modified, otherwise false.

Remarks

Indicates is the object has been set as modified or not. Useful for incremental updates (e.g. appendMode).

IsName()

Checks if this PdfObject is of the type PdfName.

public virtual bool IsName()

Returns

bool

true or false

IsNull()

Checks if this PdfObject is of the type PdfNull.

public virtual bool IsNull()

Returns

bool

true or false

IsNumber()

Checks if this PdfObject is of the type PdfNumber.

public virtual bool IsNumber()

Returns

bool

true or false

IsReleaseForbidden()

Checks if it's forbidden to release this PdfObject instance.

public virtual bool IsReleaseForbidden()

Returns

bool

true if releasing this object is forbidden, otherwise false

Remarks

Checks if it's forbidden to release this PdfObject instance. Some objects are vital for the living period of PdfDocument or may be prevented from releasing by high-level entities dealing with the objects. Also it's not possible to release the objects that have been modified.

IsStream()

Checks if this PdfObject is of the type PdfStream.

public virtual bool IsStream()

Returns

bool

true or false

IsString()

Checks if this PdfObject is of the type PdfString.

public virtual bool IsString()

Returns

bool

true or false

MakeIndirect(PdfDocument)

Marks object to be saved as indirect.

public virtual PdfObject MakeIndirect(PdfDocument document)

Parameters

document PdfDocument

a document the indirect reference will belong to.

Returns

PdfObject

object itself.

MakeIndirect(PdfDocument, PdfIndirectReference)

Marks object to be saved as indirect.

public virtual PdfObject MakeIndirect(PdfDocument document, PdfIndirectReference reference)

Parameters

document PdfDocument

a document the indirect reference will belong to.

reference PdfIndirectReference

indirect reference which will be associated with this document

Returns

PdfObject

object itself.

NewInstance()

Creates new instance of object.

protected abstract PdfObject NewInstance()

Returns

PdfObject

new instance of object.

Release() 

public virtual void Release()

SetIndirectReference(PdfIndirectReference) 

protected virtual PdfObject SetIndirectReference(PdfIndirectReference indirectReference)

Parameters

indirectReference PdfIndirectReference

Returns

PdfObject

SetModified()

Sets the 'modified' flag to the indirect object, the flag denotes that the object was modified since the document opening.

public virtual PdfObject SetModified()

Returns

PdfObject

this PdfObject instance.

Remarks

Sets the 'modified' flag to the indirect object, the flag denotes that the object was modified since the document opening. It is recommended to set this flag after changing any PDF object.

For example flag is used in the append mode (see UseAppendMode() ). In append mode the whole document is preserved as is, and only changes to the document are appended to the end of the document file. Because of this, only modified objects need to be flushed and are allowed to be flushed (i.e. to be written).

SetState(short)

Sets special states of current object.

protected virtual PdfObject SetState(short state)

Parameters

state short

special flag of current object

Returns

PdfObject

this PdfObject