PdfDictionary is the Pdf dictionary object.
*
* A dictionary is an associative table containing pairs of objects. The first element
* of each pair is called the key and the second element is called the value.
* Unlike dictionaries in the PostScript language, a key must be a PdfName.
* A value can be any kind of PdfObject, including a dictionary. A dictionary is
* generally used to collect and tie together the attributes of a complex object, with each
* key-value pair specifying the name and value of an attribute.
* A dictionary is represented by two left angle brackets (<<), followed by a sequence of
* key-value pairs, followed by two right angle brackets (>>).
* This object is described in the 'Portable Document Format Reference Manual version 1.3'
* section 4.7 (page 40-41).
*
*
* @see PdfObject
* @see PdfName
* @see BadPdfFormatException
*/
public class PdfDictionary : PdfObject {
// static membervariables (types of dictionary's)
/** This is a possible type of dictionary */
public static PdfName FONT = PdfName.FONT;
/** This is a possible type of dictionary */
public static PdfName OUTLINES = PdfName.OUTLINES;
/** This is a possible type of dictionary */
public static PdfName PAGE = PdfName.PAGE;
/** This is a possible type of dictionary */
public static PdfName PAGES = PdfName.PAGES;
/** This is a possible type of dictionary */
public static PdfName CATALOG = PdfName.CATALOG;
// membervariables
/** This is the type of this dictionary */
private PdfName dictionaryType = null;
/** This is the hashmap that contains all the values and keys of the dictionary */
protected internal Hashtable hashMap;
// constructors
/**
* Constructs an empty PdfDictionary-object.
*/
public PdfDictionary() : base(DICTIONARY) {
hashMap = new Hashtable();
}
/**
* Constructs a PdfDictionary-object of a certain type.
*
* @param type a PdfName
*/
public PdfDictionary(PdfName type) : this() {
dictionaryType = type;
Put(PdfName.TYPE, dictionaryType);
}
// methods overriding some methods in PdfObject
/**
* Returns the PDF representation of this PdfDictionary.
*
* @return an array of byte
*/
public override void ToPdf(PdfWriter writer, Stream os) {
os.WriteByte((byte)'<');
os.WriteByte((byte)'<');
// loop over all the object-pairs in the Hashtable
PdfObject value;
foreach (PdfName key in hashMap.Keys) {
value = (PdfObject) hashMap[key];
key.ToPdf(writer, os);
int type = value.Type;
if (type != PdfObject.ARRAY && type != PdfObject.DICTIONARY && type != PdfObject.NAME && type != PdfObject.STRING)
os.WriteByte((byte)' ');
value.ToPdf(writer, os);
}
os.WriteByte((byte)'>');
os.WriteByte((byte)'>');
}
// methods concerning the Hashtable member value
/**
* Adds a PdfObject and its key to the PdfDictionary.
* If the value is null or PdfNull the key is deleted.
*
* @param key key of the entry (a PdfName)
* @param value value of the entry (a PdfObject)
*/
public void Put(PdfName key, PdfObject value) {
if (value == null || value.IsNull())
hashMap.Remove(key);
else
hashMap[key] = value;
}
/**
* Adds a PdfObject and its key to the PdfDictionary.
* If the value is null it does nothing.
*
* @param key key of the entry (a PdfName)
* @param value value of the entry (a PdfObject)
*/
public void PutEx(PdfName key, PdfObject value) {
if (value == null)
return;
Put(key, value);
}
/**
* Removes a PdfObject and its key from the PdfDictionary.
*
* @param key key of the entry (a PdfName)
*/
public void Remove(PdfName key) {
hashMap.Remove(key);
}
/**
* Gets a PdfObject with a certain key from the PdfDictionary.
*
* @param key key of the entry (a PdfName)
* @return the previous PdfObject corresponding with the key
*/
public PdfObject Get(PdfName key) {
return (PdfObject) hashMap[key];
}
// methods concerning the type of Dictionary
/**
* Checks if a Dictionary is of the type FONT.
*
* @return true if it is, false if it isn't.
*/
public bool IsFont() {
return FONT.Equals(dictionaryType);
}
/**
* Checks if a Dictionary is of the type PAGE.
*
* @return true if it is, false if it isn't.
*/
public bool IsPage() {
return PAGE.Equals(dictionaryType);
}
/**
* Checks if a Dictionary is of the type PAGES.
*
* @return true if it is, false if it isn't.
*/
public bool IsPages() {
return PAGES.Equals(dictionaryType);
}
/**
* Checks if a Dictionary is of the type CATALOG.
*
* @return true if it is, false if it isn't.
*/
public bool IsCatalog() {
return CATALOG.Equals(dictionaryType);
}
/**
* Checks if a Dictionary is of the type OUTLINES.
*
* @return true if it is, false if it isn't.
*/
public bool IsOutlineTree() {
return OUTLINES.Equals(dictionaryType);
}
public void Merge(PdfDictionary other) {
foreach (object key in other.hashMap.Keys) {
hashMap[key] = other.hashMap[key];
}
}
public void MergeDifferent(PdfDictionary other) {
foreach (Object key in other.hashMap.Keys) {
if (!hashMap.ContainsKey(key)) {
hashMap[key] = other.hashMap[key];
}
}
}
public ICollection Keys {
get {
return hashMap.Keys;
}
}
public int Size {
get {
return hashMap.Count;
}
}
public bool Contains(PdfName key) {
return hashMap.ContainsKey(key);
}
public virtual IDictionaryEnumerator GetEnumerator() {
return hashMap.GetEnumerator();
}
public override String ToString() {
if (Get(PdfName.TYPE) == null) return "Dictionary";
return "Dictionary of type: " + Get(PdfName.TYPE);
}
/**
* This function behaves the same as 'get', but will never return an indirect reference,
* it will always look such references up and return the actual object.
* @param key
* @return null, or a non-indirect object
*/
public PdfObject GetDirectObject(PdfName key) {
return PdfReader.GetPdfObject(Get(key));
}
/**
* All the getAs functions will return either null, or the specified object type
* This function will automatically look up indirect references. There's one obvious
* exception, the one that will only return an indirect reference. All direct objects
* come back as a null.
* Mark A Storer (2/17/06)
* @param key
* @return the appropriate object in its final type, or null
*/
public PdfDictionary GetAsDict(PdfName key) {
PdfDictionary dict = null;
PdfObject orig = GetDirectObject(key);
if (orig != null && orig.IsDictionary())
dict = (PdfDictionary) orig;
return dict;
}
public PdfArray GetAsArray(PdfName key) {
PdfArray array = null;
PdfObject orig = GetDirectObject(key);
if (orig != null && orig.IsArray())
array = (PdfArray) orig;
return array;
}
public PdfStream GetAsStream(PdfName key) {
PdfStream stream = null;
PdfObject orig = GetDirectObject(key);
if (orig != null && orig.IsStream())
stream = (PdfStream) orig;
return stream;
}
public PdfString GetAsString(PdfName key) {
PdfString str = null;
PdfObject orig = GetDirectObject(key);
if (orig != null && orig.IsString())
str = (PdfString) orig;
return str;
}
public PdfNumber GetAsNumber(PdfName key) {
PdfNumber number = null;
PdfObject orig = GetDirectObject(key);
if (orig != null && orig.IsNumber())
number = (PdfNumber) orig;
return number;
}
public PdfName GetAsName(PdfName key) {
PdfName name = null;
PdfObject orig = GetDirectObject(key);
if (orig != null && orig.IsName())
name = (PdfName) orig;
return name;
}
public PdfBoolean GetAsBoolean(PdfName key) {
PdfBoolean b = null;
PdfObject orig = GetDirectObject(key);
if (orig != null && orig.IsBoolean())
b = (PdfBoolean)orig;
return b;
}
public PdfIndirectReference GetAsIndirectObject( PdfName key ) {
PdfIndirectReference refi = null;
PdfObject orig = Get(key); // not getDirect this time.
if (orig != null && orig.IsIndirect())
refi = (PdfIndirectReference) orig;
return refi;
}
}
}