20 lua与json

Lua-cjson库的官方网站

https://www.kyne.com.au/~mark/software/lua-cjson.php

可以用luarocks安装cjson库

luarocks install lua-cjson

例子1 decode--将json字符串解析成lua-table类型

json_text = '[true, {"foo":"bar"}]'
json_value = cjson.decode(json_text)
-- Returns: '[true,{"foo":"bar"}]'

for key, value in pairs(json_value) do
    if key == 1 then
        print(key, value)
    elseif key == 2 then
        for k, v in pairs(value) do
            print(k, v)
        end
    end
end

结果如下：

1       true
foo     bar

local cjson = require "cjson"
local sampleJson = [[{"age":"23","testArray":{"array":[8,9,11,14,25]},"Himi":"himigame.com"}]];
--解析json字符串
local data = cjson.decode(sampleJson);
--打印json字符串中的age字段
print(data["age"]);
--打印数组中的第一个值(lua默认是从0开始计数)
print(data["testArray"]["array"][1]);

例子2 encode--将lua-table类型装换成json字符串

local cjson = require "cjson"

list = {foo = "bar"}

json_str = cjson.encode(list)

print(json_str)

结果如下：

{"foo":"bar"}

local cjson = require "cjson"
local retTable = {};    --最终产生json的表
--顺序数值
local intDatas = {};
intDatas[1] = 100;
intDatas[2] = "100";
--数组
local aryDatas = {};
aryDatas[1] = {};
aryDatas[1]["键11"] = "值11";
aryDatas[1]["键12"] = "值12";
aryDatas[2] = {};
aryDatas[2]["键21"] = "值21";
aryDatas[2]["键22"] = "值22";
--对Table赋值
retTable["键1"] = "值1";
retTable[2] = 123;
retTable["int_datas"] = intDatas;
retTable["aryDatas"] = aryDatas;
--将表数据编码成json字符串
local jsonStr = cjson.encode(retTable);
print(jsonStr);
--结果是:{"int_datas":[100,"100"],"2":123,"键1":"值1","aryDatas":[{"键12":"值12","键11":"值11"},{"键21":"值21","键22":"值22"}]}