PeekString - Learn To Code - PlayBASIC Documentation

PeekString

String$ = PeekString(Address, Length)

Parameters:

Address = The Address in memory where this data should be stored
Length = The Number of characters you wish to read from memory. (length 0, reads a null terminated string)

Returns:

String$ = The string that was read

The PeekString functions will read a string of characters directly from memory.

Setting the Length parameter to zero will make PeekString read a null terminated string.

FACTS:

      * You can peek any memory location.

     * Care must be taken when reading directly from memory. Attempting to access memory that is not part of your program will most likely cause your program to crash.

      * Strings are limited to a maximun length of 32768 characters (bytes)

      * Also See Pointer

Mini Tutorial:

This example creates a bank, grabs this banks memory address (the address of the first byte in memory), pokes various test values and strings into memory, then finally reads them back.

; Create Bank #1 and allocate 100 bytes of system memory for it
  CreateBank 1,100

; Grab the actual address (the pointer) of this banks memory.
  Address=GetBankPtr(1)

; Once you have the address of something in memory, you can now
; directly read/write information in it.

; While this gives the user great freedom, it also means you can
; crash your program if your not careful.


; Poke the 8bit byte value 255 into memory
  PokeByte Address,255

; Poke the 16bit Word value 64000 into memory
  PokeWord Address+1,64000

; Poke the 32bit INteger value $aabbccdd into memory
  PokeInt Address+3,$aabbccdd

; Poke the 32bit Floating Point value 123.456 into memory
  PokeFloat Address+7, 123.456


; Poke the a null terminated string "Hello World" into memory
  PokeString Address+12, "Hello World",0



; Peek and display our byte from memory
  Print PeekByte(Address)

; Peek and display our word from memory
  Print PeekWord(Address+1)

; Peek and display our Integer value from memory
  Print Hex$(PeekInt(Address+3))

; Peek and display our Floating Point value from memory
  Print PeekFloat(Address+7)

; Peek and display our null terminated string from memory
  Print PeekString(Address+12,0)


; Display the Screen and wait for the user to press a key
  Sync
  WaitKey

This example would output.

  255
  64000
  $aabbccdd
  123.456
  Hellow World


Related Info:	PeekByte \| PeekFloat \| PeekInt \| PeekWord \| PokeByte \| PokeFloat \| PokeInt \| PokeString \| PokeWord :