我需要做一个简单的字符串分割,但似乎没有一个函数,我测试的手动方式似乎不起作用。我该怎么做呢?


当前回答

就像字符串一样。Gmatch将查找字符串中的模式,这个函数将查找模式之间的内容:

function string:split(pat)
  pat = pat or '%s+'
  local st, g = 1, self:gmatch("()("..pat..")")
  local function getter(segs, seps, sep, cap1, ...)
    st = sep and seps + #sep
    return self:sub(segs, (seps or 0) - 1), cap1 or sep, ...
  end
  return function() if st then return getter(st, g()) end end
end

默认情况下,它返回由空格分隔的任何内容。

其他回答

你可以使用penlight图书馆。它有一个使用分隔符分割字符串的函数,输出列表。

它实现了许多我们在编程时可能需要和Lua中缺少的功能。

下面是使用它的示例。

> 
> stringx = require "pl.stringx"
> 
> str = "welcome to the world of lua"
> 
> arr = stringx.split(str, " ")
> 
> arr
{welcome,to,the,world,of,lua}
> 

下面是一个在Lua 4.0中工作的例程,返回inputstr中由sep分隔的子字符串的表t:

function string_split(inputstr, sep)
    local inputstr = inputstr .. sep
    local idx, inc, t = 0, 1, {}
    local idx_prev, substr
    repeat 
        idx_prev = idx
        inputstr = strsub(inputstr, idx + 1, -1)    -- chop off the beginning of the string containing the match last found by strfind (or initially, nothing); keep the rest (or initially, all)
        idx = strfind(inputstr, sep)                -- find the 0-based r_index of the first occurrence of separator 
        if idx == nil then break end                -- quit if nothing's found
        substr = strsub(inputstr, 0, idx)           -- extract the substring occurring before the separator (i.e., data field before the next delimiter)
        substr = gsub(substr, "[%c" .. sep .. " ]", "") -- eliminate control characters, separator and spaces
        t[inc] = substr             -- store the substring (i.e., data field)
        inc = inc + 1               -- iterate to next
    until idx == nil
    return t
end

这个简单的测试

inputstr = "the brown lazy fox jumped over the fat grey hen ... or something."
sep = " " 
t = {}
t = string_split(inputstr,sep)
for i=1,15 do
    print(i, t[i])
end

收益率:

--> t[1]=the
--> t[2]=brown
--> t[3]=lazy
--> t[4]=fox
--> t[5]=jumped
--> t[6]=over
--> t[7]=the
--> t[8]=fat
--> t[9]=grey
--> t[10]=hen
--> t[11]=...
--> t[12]=or
--> t[13]=something.

只是坐在分隔符上

local str = 'one,two'
local regxEverythingExceptComma = '([^,]+)'
for x in string.gmatch(str, regxEverythingExceptComma) do
    print(x)
end

如果你只想遍历这些令牌,这是非常简洁的:

line = "one, two and 3!"

for token in string.gmatch(line, "[^%s]+") do
   print(token)
end

输出:

一个, 两个 而且 3!

简单解释:“[^%s]+”模式匹配空格字符之间的每个非空字符串。

这个问题已经很晚了,但如果有人想要一个处理分裂数量的版本,你想要.....

-- Split a string into a table using a delimiter and a limit
string.split = function(str, pat, limit)
  local t = {}
  local fpat = "(.-)" .. pat
  local last_end = 1
  local s, e, cap = str:find(fpat, 1)
  while s do
    if s ~= 1 or cap ~= "" then
      table.insert(t, cap)
    end

    last_end = e+1
    s, e, cap = str:find(fpat, last_end)

    if limit ~= nil and limit <= #t then
      break
    end
  end

  if last_end <= #str then
    cap = str:sub(last_end)
    table.insert(t, cap)
  end

  return t
end