CODEWITHSUNDEEP
lua
jprbest
jprbest

Reputation: 737

add Hex to a bytes table in lua

i have the following hex C0010203 i need to store it in bytes in a bytes table

i forgot the syntax i remember 

bytes={}
bytes={0xC0 , something here}
 or 
bytes = {something here, 0xC0}

thanks for the help

Upvotes: 0

Views: 3857

Answers (3)

gwell
gwell

Reputation: 2753

In Lua there is no "byte table". There is, however, a table with the bytes as numbers.

bytes={0xC0, 0x01, 0x02, 0x03}

And here are some other options:

--A table with the bytes as numbers in little-endian:
bytes={0x03, 0x02, 0x01, 0xC0}

--A string of characters that contain the bytes:
bytes=string.char(0xC0, 0x01, 0x02, 0x03)

--A string of characters that contain the bytes in little-endian:
bytes=string.char(0x03, 0x02, 0x01, 0xC0)

--A table of single character strings for each byte:
bytes={string.char(0xC0),string.char(0x01),string.char(0x02),string.char(0x02)}

--A table of single character strings for each byte in little-endian:
bytes={string.char(0x03),string.char(0x02),string.char(0x01),string.char(0xC0)}

Upvotes: 0

jpjacobs
jpjacobs

Reputation: 9549

My throw at this would be:

s="C001020304"
t={}
for k in s:gmatch"(%x%x)" do
    table.insert(t,tonumber(k,16))
end

Upvotes: 1

user594138
user594138

Reputation:

It's a bit unclear to me what you mean, something like this?

tomte@tomte ~ $ lua
Lua 5.1.4  Copyright (C) 1994-2008 Lua.org, PUC-Rio
> bytes={}
> bytes["something here"]=0xC0
> print(bytes["something here"])
192
>

EDIT: I see, possibly crude but working solution (without bounds checking, you have to adjust the code for strings that don't have an even length or don't contain hex-numbers);

tomte@tomte ~ $ lua
Lua 5.1.4  Copyright (C) 1994-2008 Lua.org, PUC-Rio
> i=1
> j=1
> t={}
> s="C0010203"
> while true do
>> t[j] = 0 + ("0x" .. string.sub(s,i,i+1))
>> j=j+1
>> i=i+2
>> if(i>string.len(s)) then break end
>> end
> print (t[1])
192
> print (t[2])
1
> print (t[3])
2
> print (t[4])
3

Upvotes: 0

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