Loop through character of a string in Assembly

Question

If I have a list of strings, how can I loop through each character of each string? say a list data

data     db "00000123", NULL, "00000213"

how do I go about accessing each member? I know the length of each string is a constant length of 9, and I understand for normal types it would be byte[data+rsi] where rsi is my counter, but what does this do when strings are in play?

; loop
  ; get character from string
  ; check if character is end
  ; if yes then jump end
  ; do stuff with char
; end

@IgnacioVazquez-Abrams I'm confused as how to access them. Would `byte[data]` be **0** and `byte[data+7]` be **3**? are all of the characters simply contiguous in the list? — Syntactic Fructose, Feb 11 '15 at 04:25
@IgnacioVazquez-Abrams thanks, one more question however. If I accessed `byte[data]` would I be given `0` or `"0"`? In assembly a byte is a byte correct? I should simply be able to move each character of the string in a variable and be able to treat it as a number I could perform an operation on? If you'd like to sum up my first commend and answer this in an actual answer question I'd be happy to accept it for this post. — Syntactic Fructose, Feb 11 '15 at 04:31
You would be given '0' (0x30) because that's what you've written. — Ignacio Vazquez-Abrams, Feb 11 '15 at 04:32
@IgnacioVazquez-Abrams I understand now. Thanks! If you make an answer I'll accept it — Syntactic Fructose, Feb 11 '15 at 04:33

score 1 · Accepted Answer · answered Feb 11 '15 at 04:34

1

Data written contiguously in an assembly language file will be contiguous in memory, and as such data will point to '0' (0x30), data+7 will point to '3' (0x33), and each of the locations in between will point to their corresponding characters in turn.

answered Feb 11 '15 at 04:34

Ignacio Vazquez-Abrams

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Loop through character of a string in Assembly

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