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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{Include files}
	12
	13	<wx/hash.h>
	14
	15	\wxheading{Example}
	16
	17	Below is an example of using a hash table.
	18
	19	\begin{verbatim}
	20	wxHashTable table(KEY_STRING);
	21
	22	wxPoint *point = new wxPoint(100, 200);
	23	table.Put("point 1", point);
	24
	25	....
	26
	27	wxPoint found_point = (wxPoint )table.Get("point 1");
	28	\end{verbatim}
	29
	30	A hash table is implemented as an array of pointers to lists. When no
	31	data has been stored, the hash table takes only a little more space than
	32	this array (default size is 1000). When a data item is added, an
	33	integer is constructed from the integer or string key that is within the
	34	bounds of the array. If the array element is NULL, a new (keyed) list is
	35	created for the element. Then the data object is appended to the list,
	36	storing the key in case other data objects need to be stored in the list
	37	also (when a `collision' occurs).
	38
	39	Retrieval involves recalculating the array index from the key, and searching
	40	along the keyed list for the data object whose stored key matches the passed
	41	key. Obviously this is quicker when there are fewer collisions, so hashing
	42	will become inefficient if the number of items to be stored greatly exceeds
	43	the size of the hash table.
	44
	45	\wxheading{See also}
	46
	47	\helpref{wxList}{wxlist}
	48
	49	\latexignore{\rtfignore{\wxheading{Members}}}
	50
	51	\membersection{wxHashTable::wxHashTable}
	52
	53	\func{}{wxHashTable}{\param{unsigned int}{ key\_type}, \param{int}{ size = 1000}}
	54
	55	Constructor. {\it key\_type} is one of wxKEY\_INTEGER, or wxKEY\_STRING,
	56	and indicates what sort of keying is required. {\it size} is optional.
	57
	58	\membersection{wxHashTable::\destruct{wxHashTable}}
	59
	60	\func{}{\destruct{wxHashTable}}{\void}
	61
	62	Destroys the hash table.
	63
	64	\membersection{wxHashTable::BeginFind}
	65
	66	\func{void}{BeginFind}{\void}
	67
	68	The counterpart of {\it Next}. If the application wishes to iterate
	69	through all the data in the hash table, it can call {\it BeginFind} and
	70	then loop on {\it Next}.
	71
	72	\membersection{wxHashTable::Clear}
	73
	74	\func{void}{Clear}{\void}
	75
	76	Clears the hash table of all nodes (but as usual, doesn't delete user data).
	77
	78	\membersection{wxHashTable::Delete}
	79
	80	\func{wxObject *}{Delete}{\param{long}{ key}}
	81
	82	\func{wxObject *}{Delete}{\param{const wxString\& }{ key}}
	83
	84	Deletes entry in hash table and returns the user's data (if found).
	85
	86	\membersection{wxHashTable::DeleteContents}
	87
	88	\func{void}{DeleteContents}{\param{bool}{ flag}}
	89
	90	If set to TRUE data stored in hash table will be deleted when hash table object
	91	is destroyed.
	92
	93
	94	\membersection{wxHashTable::Get}
	95
	96	\func{wxObject *}{Get}{\param{long}{ key}}
	97
	98	\func{wxObject }{Get}{\param{const char}{ key}}
	99
	100	Gets data from the hash table, using an integer or string key (depending on which
	101	has table constructor was used).
	102
	103	\membersection{wxHashTable::MakeKey}
	104
	105	\func{long}{MakeKey}{\param{const wxString\& }{string}}
	106
	107	Makes an integer key out of a string. An application may wish to make a key
	108	explicitly (for instance when combining two data values to form a key).
	109
	110	\membersection{wxHashTable::Next}
	111
	112	\func{wxNode *}{Next}{\void}
	113
	114	If the application wishes to iterate through all the data in the hash
	115	table, it can call {\it BeginFind} and then loop on {\it Next}. This function
	116	returns a {\bf wxNode} pointer (or NULL if there are no more nodes). See the
	117	description for \helpref{wxNode}{wxnode}. The user will probably only wish to use the
	118	{\bf wxNode::Data} function to retrieve the data; the node may also be deleted.
	119
	120	\membersection{wxHashTable::Put}
	121
	122	\func{void}{Put}{\param{long}{ key}, \param{wxObject *}{object}}
	123
	124	\func{void}{Put}{\param{const char}{ key}, \param{wxObject }{object}}
	125
	126	Inserts data into the hash table, using an integer or string key (depending on which
	127	has table constructor was used). The key string is copied and stored by the hash
	128	table implementation.
	129
	130	\membersection{wxHashTable::GetCount}
	131
	132	\constfunc{size\_t}{GetCount}{\void}
	133
	134	Returns the number of elements in the hash table.
	135