/// <summary>
/// Gets a cross reference entry from an object identifier.
/// Returns null if no object with the specified ID exists in the object table.
/// </summary>
public PdfReference this[PdfObjectID objectID]
{
get
{
PdfReference iref;
ObjectTable.TryGetValue(objectID, out iref);
return(iref);
}
}
/// <summary>
/// Indicates whether this instance and a specified object are equal.
/// </summary>
public override bool Equals(object obj)
{
if (obj is PdfObjectID)
{
PdfObjectID id = (PdfObjectID)obj;
if (_objectNumber == id._objectNumber)
{
return(_generationNumber == id._generationNumber);
}
}
return(false);
}
/// <summary>
/// Compares the current object id with another object.
/// </summary>
public int CompareTo(object obj)
{
if (obj is PdfObjectID)
{
PdfObjectID id = (PdfObjectID)obj;
if (_objectNumber == id._objectNumber)
{
return(_generationNumber - id._generationNumber);
}
return(_objectNumber - id._objectNumber);
}
return(1);
}
/// <summary>
/// Finds a page by its id. Transforms it to PdfPage if necessary.
/// </summary>
internal PdfPage FindPage(PdfObjectID id) // TODO: public?
{
PdfPage page = null;
foreach (PdfItem item in PagesArray)
{
PdfReference reference = item as PdfReference;
if (reference != null)
{
PdfDictionary dictionary = reference.Value as PdfDictionary;
if (dictionary != null && dictionary.ObjectID == id)
{
page = dictionary as PdfPage ?? new PdfPage(dictionary);
break;
}
}
}
return(page);
}
/// <summary>
/// Sets the object and generation number.
/// Setting the object identifier makes this object an indirect object, i.e. the object gets
/// a PdfReference entry in the PdfReferenceTable.
/// </summary>
internal void SetObjectID(int objectNumber, int generationNumber)
{
PdfObjectID objectID = new PdfObjectID(objectNumber, generationNumber);
// TODO: check imported
if (_iref == null)
{
_iref = _document._irefTable[objectID];
}
if (_iref == null)
{
// ReSharper disable once ObjectCreationAsStatement because the new object is set to this object
// in the constructor of PdfReference.
new PdfReference(this);
Debug.Assert(_iref != null);
_iref.ObjectID = objectID;
}
_iref.Value = this;
_iref.Document = _document;
}
/// <summary>
/// Indicates whether the specified object identifier is in the table.
/// </summary>
public bool Contains(PdfObjectID objectID)
{
return(ObjectTable.ContainsKey(objectID));
}
