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Hash Table Functions:

_HDICT_NEW() -> pHt                      -  Create a new hash table and return the handle

_HDICT_KEY_COMPARE(key1,key2) -> lEqual  -  Compare 2 keys (num,char or date) and return .T. if are equivalents

_HDICT_DESTROY(pHt)                      -  Release memory used to store the hash table.

_HDICT_SETPROP(pHt,key,val)              -  Add new entry to the hash table and discard previous if any.

_HDICT_GETPROP(pHt,key)                  -  Retrieve a value or NIL if entry not exist.

_HDICT_REMOVEPROP(pHt,key)               -  Remove a entry if exist

_HDICT_REMOVEALL(pHt)                    -  Remove all entries

_HDICT_COUNT(pHt)                        -  Count existing entries in the hash table

_HDICT_ITERATE_STEP(pHt,@pIterator,@item,@key)- Return 1 item at time from the hash table storage

_HDICT_ITERATE_CB( pHt , codeblock , @cargo ) - Evaluate a codeblock across all items

 

 

You have to pay attention on some special explanations on those functions on there own site:

_HDICT_ITERATE_STEP()

_HDICT_ITERATE_CB()

 

_HDICT_* functions and multi-thread

 

_HDICT_* functions don't provide built in multithread serialization !

But your classes can provide the required multithread support in a easy manner just using SYNC methods

 

Example:

 

CLASS Dictionary

   EXPORTED:

   VAR ht

   INLINE METHOD init()           ; 

          ::ht := _HDICT_NEW()    ;

          return Self

   INLINE SYNC METHOD Destroy()   ; 

          _HDICT_DESTROY(::ht)    ;

          ::ht := NIL             ;  

          return Self

   INLINE SYNC METHOD Put(key,val); 

          return _HDICT_SETPROP(::ht,key,val)

   INLINE SYNC METHOD Get(key)    ; 

          return _HDICT_GETPROP(::ht,key)

   INLINE SYNC METHOD Del(key)    ; 

          return _HDICT_REMOVEPROP(::ht,key)

   INLINE SYNC METHOD Zap()       ; 

          return _HDICT_REMOVEALL(::ht)

ENDCLASS