pc_tiantian/core/luaScript/Tools/stringEx.lua

-- 处理UTF8中文，显示长度一个中文等于两个英文，编码长度一个中文等于2，3，4个英文，以英文单位计算长度
local function _analysisUTF8(str)
    local width = 0
    local i = 1
    local UTF8Map = {}
    while (i <= #str) do
        local curByte = string.byte(str, i)
        local byteCount = 1
        if curByte >= 240 then
            byteCount = 4
        elseif curByte > 225 then
            byteCount = 3
        elseif curByte > 192 then
            byteCount = 2
        end
         
        local char = string.sub(str, i, i+byteCount-1)
		if byteCount == 4 then
			char = "□"
		end
        table.insert(UTF8Map, char)                                       --看看这个字是什么
        i = i + byteCount                                              -- 重置下一字节的索引
        if byteCount == 1 then
            width = width + 1                                             -- 字符的个数（长度）
        else
            width = width + 2
        end
    end
    return width, UTF8Map
end

local function filter_spec_chars(s)
    local ss = {}
    local k = 1
    while true do
        if k > #s then break end
        local c = string.byte(s,k)
        if not c then break end
        if c<192 then
            --if (c>=48 and c<=57) or (c>= 65 and c<=90) or (c>=97 and c<=122) then
                table.insert(ss, string.char(c))
            --end
            k = k + 1
        elseif c<224 then
            k = k + 2
			table.insert(ss, string.char(63))
        elseif c<240 then
            if c>=228 and c<=233 then
                local c1 = string.byte(s,k+1)
                local c2 = string.byte(s,k+2)
                if c1 and c2 then
                    local a1,a2,a3,a4 = 128,191,128,191
                    if c == 228 then a1 = 184
                    elseif c == 233 then a2,a4 = 190,c1 ~= 190 and 191 or 165
                    end
                    if c1>=a1 and c1<=a2 and c2>=a3 and c2<=a4 then
                        table.insert(ss, string.char(c,c1,c2))
                    end
                end
            end
            k = k + 3
        elseif c<248 then
            k = k + 4
			table.insert(ss, string.char(63))
        elseif c<252 then
            k = k + 5
			table.insert(ss, string.char(63))
        elseif c<254 then
            k = k + 6
			table.insert(ss, string.char(63))
        end
    end
    --return 4,table.concat(ss)
	return 4,ss
end

-- 获取当前字符展示宽度
function string.getUTF8Width(str)
    local width, _ = _analysisUTF8(str)
    return width
end

-- 按照关键词把string转化为table
function string.toTableByString(str, strKey)
    local strTable = {}
    str = tostring(str)
    function test(str)
        if str == "" then return end
        local str1, str2 = "", ""
        local strLen = string.len(str)
        local begNum, endNum = string.find(str, strKey)
        if type(begNum) ~= "number" or type(endNum) ~= "number" then
            str1 = str
        else
            if type(begNum) == "number" and begNum > 1 then
                str1 = string.sub(str, 1, begNum - 1)
            end

            if type(endNum) == "number" and endNum < strLen then
                str2 = string.sub(str, endNum + 1, strLen)
            end
        end
        table.insert(strTable, str1)
        test(str2)
    end
    test(str)
    return strTable
end

function string.getShortName(str,size)
	local width, UTF8Map = _analysisUTF8(str)
	local num,shortName = 0,""
	local max = #UTF8Map--size < max and
	if type(UTF8Map) == "table" and next(UTF8Map) then
		for _,v in ipairs(UTF8Map) do
			if num < size then
				if v then
					shortName = shortName .. v
					num = num + 1
				end
			end
		end
		if max > size then
			shortName = shortName.."..."
		end
		return shortName
	else
		for _,v in ipairs(UTF8Map) do
			if num < size then
				if v then
					shortName = shortName .. v
					num = num + 1
				end
			end
		end
		return shortName
	end
end

--另一种方式过滤
function string.getShortName2(str,size)
	local width, UTF8Map = filter_spec_chars(str)
	local num,shortName = 0,""
	local max = #UTF8Map
	if size < max and type(UTF8Map) == "table" and next(UTF8Map) then
		for _,v in ipairs(UTF8Map) do
			if num < size then
				if v then
					shortName = shortName .. v
					num = num + 1
				end
			end
		end
		if max > size then
			shortName = shortName.."..."
		end
		return shortName
	else
		for _,v in ipairs(UTF8Map) do
			if num < size then
				if v then
					shortName = shortName .. v
					num = num + 1
				end
			end
		end
		return shortName
	end
end

--[[
逆序截取字符串
]]
function string.subStringReverse(str, k)
    local ts = string.reverse(str)
    local _,i = string.find(ts, k)
    local m = string.len(ts) - i + 1
    return string.sub(str, 1, m)  --返回字符串str字符k之前的部分
end