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	1	\section{\class{wxHashTable}}\label{wxhashtable}
	2
	3	This class provides hash table functionality for wxWindows, and for an
	4	application if it wishes. Data can be hashed on an integer or string
	5	key.
	6
	7	\wxheading{Derived from}
	8
	9	\helpref{wxObject}{wxobject}
	10
	11	\wxheading{Example}
	12
	13	Below is an example of using a hash table.
	14
	15	\begin{verbatim}
	16	wxHashTable table(KEY_STRING);
	17
	18	wxPoint *point = new wxPoint(100, 200);
	19	table.Put("point 1", point);
	20
	21	....
	22
	23	wxPoint found_point = (wxPoint )table.Get("point 1");
	24	\end{verbatim}
	25
	26	A hash table is implemented as an array of pointers to lists. When no
	27	data has been stored, the hash table takes only a little more space than
	28	this array (default size is 1000). When a data item is added, an
	29	integer is constructed from the integer or string key that is within the
	30	bounds of the array. If the array element is NULL, a new (keyed) list is
	31	created for the element. Then the data object is appended to the list,
	32	storing the key in case other data objects need to be stored in the list
	33	also (when a `collision' occurs).
	34
	35	Retrieval involves recalculating the array index from the key, and searching
	36	along the keyed list for the data object whose stored key matches the passed
	37	key. Obviously this is quicker when there are fewer collisions, so hashing
	38	will become inefficient if the number of items to be stored greatly exceeds
	39	the size of the hash table.
	40
	41	\wxheading{See also}
	42
	43	\helpref{wxList}{wxlist}
	44
	45	\latexignore{\rtfignore{\wxheading{Members}}}
	46
	47	\membersection{wxHashTable::wxHashTable}
	48
	49	\func{}{wxHashTable}{\param{unsigned int}{ key\_type}, \param{int}{ size = 1000}}
	50
	51	Constructor. {\it key\_type} is one of wxKEY\_INTEGER, or wxKEY\_STRING,
	52	and indicates what sort of keying is required. {\it size} is optional.
	53
	54	\membersection{wxHashTable::\destruct{wxHashTable}}
	55
	56	\func{}{\destruct{wxHashTable}}{\void}
	57
	58	Destroys the hash table.
	59
	60	\membersection{wxHashTable::BeginFind}
	61
	62	\func{void}{BeginFind}{\void}
	63
	64	The counterpart of {\it Next}. If the application wishes to iterate
	65	through all the data in the hash table, it can call {\it BeginFind} and
	66	then loop on {\it Next}.
	67
	68	\membersection{wxHashTable::Clear}
	69
	70	\func{void}{Clear}{\void}
	71
	72	Clears the hash table of all nodes (but as usual, doesn't delete user data).
	73
	74	\membersection{wxHashTable::Delete}
	75
	76	\func{wxObject *}{Delete}{\param{long}{ key}}
	77
	78	\func{wxObject *}{Delete}{\param{const wxString\& }{ key}}
	79
	80	Deletes entry in hash table and returns the user's data (if found).
	81
	82	\membersection{wxHashTable::Get}
	83
	84	\func{wxObject *}{Get}{\param{long}{ key}}
	85
	86	\func{wxObject *}{Get}{\param{const wxString\& }{ key}}
	87
	88	Gets data from the hash table, using an integer or string key (depending on which
	89	has table constructor was used).
	90
	91	\membersection{wxHashTable::MakeKey}
	92
	93	\func{long}{MakeKey}{\param{const wxString\& }{string}}
	94
	95	Makes an integer key out of a string. An application may wish to make a key
	96	explicitly (for instance when combining two data values to form a key).
	97
	98	\membersection{wxHashTable::Next}
	99
	100	\func{wxNode *}{Next}{\void}
	101
	102	If the application wishes to iterate through all the data in the hash
	103	table, it can call {\it BeginFind} and then loop on {\it Next}. This function
	104	returns a {\bf wxNode} pointer (or NULL if there are no more nodes). See the
	105	description for \helpref{wxNode}{wxnode}. The user will probably only wish to use the
	106	{\bf wxNode::Data} function to retrieve the data; the node may also be deleted.
	107
	108	\membersection{wxHashTable::Put}
	109
	110	\func{void}{Put}{\param{long}{ key}, \param{wxObject *}{object}}
	111
	112	\func{void}{Put}{\param{const wxString\& }{ key}, \param{wxObject *}{object}}
	113
	114	Inserts data into the hash table, using an integer or string key (depending on which
	115	has table constructor was used). The key string is copied and stored by the hash
	116	table implementation.
	117
	118