--功能：分割字符串

--参数：带分割字符串，分隔符

--返回：字符串表

function string.split(str, delimiter)

    str = tostring(str)

    delimiter = tostring(delimiter)

    if (delimiter=='') then return false end

    local pos,arr = , {}

    -- for each divider found

    for st,sp in function() return string.find(str, delimiter, pos, true) end do

        table.insert(arr, string.sub(str, pos, st - ))

        pos = sp +

    end

    table.insert(arr, string.sub(str, pos))

    return arr

end

--功能：统计字符串中字符的个数

--返回：总字符个数、英文字符数、中文字符数

function string.count(str)

  local tmpStr=str

  local _,sum=string.gsub(str,"[^\128-\193]","")

  local _,countEn=string.gsub(tmpStr,"[%z\1-\127]","")

  return sum,countEn,sum-countEn

end

--功能：计算字符串的宽度，这里一个中文等于两个英文

function string.width(str)

  local _,en,cn=string.count(str)

  return cn*+en

end

-- 功能: 把字符串扩展为长度为len,居中对齐, 其他地方以filledChar补齐

-- 参数: str 需要被扩展的字符、数字、字符串表，len 被扩展成的长度，

--       filledChar填充字符，可以为空

function string.tocenter(str, len, filledChar)

  local function tocenter(str,len,filledChar)

      str = tostring(str);

      filledChar = filledChar or " ";

      local nRestLen = len - string.width(str); -- 剩余长度

      local nNeedCharNum = math.floor(nRestLen / string.width(filledChar)); -- 需要的填充字符的数量

      local nLeftCharNum = math.floor(nNeedCharNum / ); -- 左边需要的填充字符的数量

      local nRightCharNum = nNeedCharNum - nLeftCharNum; -- 右边需要的填充字符的数量

      str = string.rep(filledChar, nLeftCharNum)..str..string.rep(filledChar, nRightCharNum); -- 补齐

      return str

  end

  if type(str)=="number" or type(str)=="string" then

      if not string.find(tostring(str),"\n") then

        return tocenter(str,len,filledChar)

      else

        str=string.split(str,"\n")

      end

  end

  if type(str)=="table" then

    local tmpStr=tocenter(str[],len,filledChar)

    for i=,#str do

      tmpStr=tmpStr.."\n"..tocenter(str[i],len,filledChar)

    end

    return tmpStr

  end

end

-- 功能: 把字符串扩展为长度为len,左对齐, 其他地方用filledChar补齐

function string.toleft(str, len, filledChar)

  local function toleft(str, len, filledChar)

    str    = tostring(str);

    filledChar  = filledChar or " ";

    local nRestLen  = len - string.width(str);        -- 剩余长度

    local nNeedCharNum = math.floor(nRestLen / string.width(filledChar)); -- 需要的填充字符的数量

    str = str..string.rep(filledChar, nNeedCharNum);     -- 补齐

    return str;

  end

  if type(str)=="number" or type(str)=="string" then

      if not string.find(tostring(str),"\n") then

        return toleft(str,len,filledChar)

      else

        str=string.split(str,"\n")

      end

  end

  if type(str)=="table" then

    local tmpStr=toleft(str[],len,filledChar)

    for i=,#str do

      tmpStr=tmpStr.."\n"..toleft(str[i],len,filledChar)

    end

    return tmpStr

  end

end

-- 功能: 把字符串扩展为长度为len,右对齐, 其他地方用filledChar补齐

function string.toright(str, len, filledChar)

  local function toright(str, len, filledChar)

    str    = tostring(str);

    filledChar  = filledChar or " ";

    local nRestLen  = len - string.width(str);        -- 剩余长度

    local nNeedCharNum = math.floor(nRestLen / string.width(filledChar)); -- 需要的填充字符的数量

    str = string.rep(filledChar, nNeedCharNum).. str;     -- 补齐

    return str;

  end

  if type(str)=="number" or type(str)=="string" then

      if not string.find(tostring(str),"\n") then

        return toright(str,len,filledChar)

      else

        str=string.split(str,"\n")

      end

  end

  if type(str)=="table" then

    local tmpStr=toright(str[],len,filledChar)

    for i=,#str do

      tmpStr=tmpStr.."\n"..toright(str[i],len,filledChar)

    end

    return tmpStr

  end

end

--测试代码

print("对齐测试\n")

print(string.tocenter(string.split("居中cc\n居中","\n"),*,"*"))

print(string.tocenter("居中cc\n居中",*))

print("\n")

print(string.toright(string.split("居右rr\n居右","\n"),*,"*"))

print(string.toright("居右rr\n居右",*))

print("\n")

print(string.toleft(string.split("居左ll\n居左","\n"),*,"*"))

print(string.toleft("居左ll\n居左",*))

function string.ltrim(str)

    return string.gsub(str, "^[ \t\n\r]+", "")

end

function string.rtrim(str)

    return string.gsub(str, "[ \t\n\r]+$", "")

end

function string.trim(str)

    str = string.gsub(str, "^[ \t\n\r]+", "")

    return string.gsub(str, "[ \t\n\r]+$", "")

end