This function allows the easy loading of a CSV File into a table of tables. It can be used in two ways, if the file has a header line this can be used to return a table with lines indexed on the header field names, in which case two tables are returned one with the data and another with the field names. Alternately all the lines in the file can be returned as a simply indexed table.

Requires: None

Code

--[[table.loadcsv @name table.loadcsv @description Loads a CSV file into a table of tables, the first line should contain descriptions @usage provide valid filename, use ipairs loop to use resulting table @param filename filename to load @param bHasHeader true if the file contains a header line, false if not, defaults to false If true @return table of tables, if a header is used, indexed by the fieldnames from the header @return table containing the header field names (if used) ]] function table.loadcsv(filename,bHasHeader) bHasHeader = bHasHeader or false local bHeader = false local function fromCSV (s) s = s .. ',' -- ending comma local t = {} -- table to collect fields local fieldstart = 1 repeat -- next field is quoted? (start with `"'?) if string.find(s, '^"', fieldstart) then local a, c local i = fieldstart repeat -- find closing quote a, i, c = string.find(s, '"("?)', i+1) until c ~= '"' -- quote not followed by quote? if not i then error('unmatched "') end local f = string.sub(s, fieldstart+1, i-1) table.insert(t, (string.gsub(f, '""', '"'))) fieldstart = string.find(s, ',', i) + 1 else -- unquoted; find next comma local nexti = string.find(s, ',', fieldstart) table.insert(t, string.sub(s, fieldstart, nexti-1)) fieldstart = nexti + 1 end until fieldstart > string.len(s) return t end local contents = {} if bHasHeader then local header = {} end for line in io.lines(filename) do local fields = fromCSV(line) local data = {} if bHasHeader then if bheader then -- Build Data Table with the Header Descriptions for i,field in ipairs(fields) do if field ~= '' then data[header[i]] = field end end table.insert(contents,data) else -- Grab Column Names header = fields bheader = true end else table.insert(contents,fields) end end return contents,header end 

 

Usage

-- Load CSV with file with header local lines,titles = table.loadcsv('my.csv',true) -- Load CSV with file with no header local lines = table.loadcsv('my.csv')