Get Array Pointer

[kevin]

  This example shows a new feature of PlayBasic V1.082.  Which allows your to grab the address( pointer) of an array in memory. You can then peek/poke this memory as you like.

 This will be mostly useful for DLL's/Plug In authors wishing to pass Arrays to their Dll's directly.  Although users could use it as way to store Mixed data within a single array.  Since you can poke/peek Bytes/Words/Integers/Floats and Strings. Obviously some care has to be taken when doing that. But, you can now do it.



   Version for PlayBASIC V1.08 (Pre 2005)  

PlayBASIC Code: [Select]

   ; Create Array Called Table()
      Dim Table(10)
      For lp=0 to 10
       Table(lp)=100+lp
      Next
  
   ; Get the Addres of this array
      Address=GetArrayPtr(table())

   ; peek the array memory and show the elements
      ShowArray(Address)

   ; manually poke some new values into this arrays memory
      print "Poking Data Directly Into This Arrays Memory"
      DataAddress=Address+PBarraystruct_size
      For lp=0 to 10
         PokeInt Dataaddress+(lp*4),2000+lp
      next  
   
   ;show the array memory again
   ShowArray(Address)
 
 sync
 waitkey
    
Function ShowArray(Address)
   print "Display Array Data"
   DataAddress=Address+PBarraystruct_size
   For lp=0 to 10
      print PeekINt(Dataaddress+(lp*4))
   next  
EndFunction

   PlayBASIC V1.64 (and above Version)  

PlayBASIC Code: [Select]

   ; ---------------------------------------------------------------   
   ; PlayBASIC V1.64 (and above Version)   
   ; ---------------------------------------------------------------   
   ;   
   ;  GetArrayPTR() includes an optional flag to either return
   ;                the arrays RAW address in memory or the address
   ;                 of the FRIST data stored at INDEX #0
   ;   
   ; ---------------------------------------------------------------   


   
   ; Create Array Called Table()
      Dim Table(10)
      For lp=0 to 10
          Table(lp)=100+lp
      Next
  
   ; Get the Address of the INDEX 0 within this array
      Address=GetArrayPtr(table(),true)

   ; peek the array memory and show the elements
      ShowArray(Address)

   ; manually poke some new values into this arrays memory
      print "Poking Data Directly Into This Arrays Memory"
      For lp=0 to 10
         PokeINT address+(lp*4),2000+lp
      next  
   
   ;show the array memory again
   ShowArray(Address)
 
 sync
 waitkey
    
Function ShowArray(Address)
   print "Display Array Data"
   For lp=0 to 10
      print PeekINT(address+(lp*4))
   next  
EndFunction

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