toml与json联系对比

前言

本文简单介绍toml；并且和json转化做对比，以及我对toml设计的理解。

参考：

TOML: 简体中文 v1.0.0

json和toml转化工具

在线JSON转toml-toml转JSON - bejson在线工具

正文

数组

说白了，就是一个变量名，有多个变量的值。值的类型，可以相同，可以不同。

integers = [ 1, 2, 3 ]
colors = [ "红", "黄", "绿" ]
nested_array_of_ints = [ [ 1, 2 ], [3, 4, 5] ]
nested_mixed_array = [ [ 1, 2 ], ["a", "b", "c"] ]
string_array = [ "所有的", '字符串', """是相同的""", '''类型''' ]# 允许混合类型的数组
numbers = [ 0.1, 0.2, 0.5, 1, 2, 5 ]
contributors = ["Foo Bar <[e-mail]>",{ name = "Baz Qux", email = "[e-mail]", url = "https://example.com/bazqux" }
]

对应josn

{"integers": [ 1,2,3 ],"colors": ["红",黄","绿"],"nested_array_of_ints": [[1,2],[3,4,5]],"nested_mixed_array": [[1,2],["a","b","c"]],"string_array": ["所有的","字符串","是相同的","类型"],"numbers": [0.1,0.2,0.5,1,2,5],"contributors": ["Foo Bar <[e-mail]>",{"name": "Baz Qux","email": "[e-mail]","url": "https://example.com/bazqux"}]
}

表

在json中对应“对象”；要注意的是json中，对象有的有名字，有的没有名字。

toml方括号，就说明用的是“表”。也就是json中的对象。

创建表的方法：

#创建了sites对象，内容有site1
[sites]
site1 = "www.runoob.com"#创建了“嵌套”对象
[dog]
[dog."tater.man"]
[dog."tater.man".type]
name = "pug"#等价于上面
dog."tater.man".type.name = "pug"

例子：

{"name":"runoob","alexa":10000,"sites": {"site1":"www.runoob.com","site2":"m.runoob.com","site3":"c.runoob.com"}
}转成toml
name = "runoob"
alexa = 10000
[sites]
site1 = "www.runoob.com"
site2 = "m.runoob.com"
site3 = "c.runoob.com"

嵌套

{"dog": {"tater": {"type": {"name": "pug"}}}
}转成toml
[dog]
[dog.tater]
[dog.tater.type]
name = "pug"
#等价于上面——没有括号
dog.tater.type.name = "pug"

demo

[merter1.VoltageSurge]STimeStamp= ["1","2","3"]ETimeStamp= ["4","5","6"][merter1.VoltageDip]STimeStamp= ["1","2","3"]ETimeStamp= ["1","2","3"][merter2.VoltageSurge]STimeStamp= ["1","2","3"]ETimeStamp= ["1","2","3"]
[merter2.VoltageDip]STimeStamp= ["1","2","3"]ETimeStamp= ["1","2","3"]const auto data = toml::parse("C:/Users/45428/Desktop/test.toml");for (const auto& kv : data.as_table()) {const toml::value& value = kv.second;// 遍历子表const toml::table& sub_table = value.as_table();for (const auto& sub_kv : sub_table) {const toml::key& sub_key = sub_kv.first;const toml::value& sub_value = sub_kv.second;const auto STimeStamp = toml::find<std::vector<string>>(sub_value, "STimeStamp");const auto ETimeStamp = toml::find<std::vector<string>>(sub_value, "ETimeStamp");}}

内联表

和“表”一样。

他的存在就是让文件变得更加紧凑相对于“表”来说。

既然是为了更紧凑，就不允许他换行。

你要内联表，就得在大括号里定义完，不允许再起一行后面增加。或者用内联表去增加一般的表。

#表
[name]
first = "Tom"
last = "Preston-Werner"
[point]
x = 1
y = 2
[animal]
type.name = "pug"#内联表——更紧凑——上下都一样
name = { first = "Tom", last = "Preston-Werner" }
point = { x = 1, y = 2 }
animal = { type.name = "pug" }

表数组

就是表里嵌套数组；

对应的json就是对象嵌套数组。

【【数组名字】】

例子：

{"products": [#数组products——两个元素{"name": "Hammer","sku": 738594937},{"name": "Nail","sku": 284758393}],"products1": [#数组products1——一个元素{"name": "Hammer","sku": 738594937}]
}#数组products
[[products]]
name = "Hammer"
sku = 738594937
[[products]]
name = "Nail"
sku = 284758393#数组products1
[[products1]]
name = "Hammer"
sku = 738594937

嵌套

[[fruits]]
name = "apple"[fruits.physical]  # 子表
color = "red"
shape = "round"[[fruits.varieties]]  # 嵌套表数组
name = "red delicious"[[fruits.varieties]]
name = "granny smith"[[fruits]]
name = "banana"[[fruits.varieties]]
name = "plantain"{"fruits": [{"name": "apple","physical": {"color": "red","shape": "round"},"varieties": [{"name": "red delicious"},{"name": "granny smith"}]},{"name": "banana","varieties": [{"name": "plantain"}]}]
}

表和表数组的区别

【对象名】：toml的表，json的对象

{"a": {}
}

【【对象名】】：toml的表数组，json的数组里放对象

{"a": [{}]
}

嵌套：

【a.b】a对象嵌套b对象

{"a": {"b": {}}
}

【【a.b】】a数组嵌套b对象

[[a.b]]{"a": {"b": [{}]}
}

嵌套的都是对象