JsonPath 简介.. | 选择所有符合条件的节点

语法

JsonPath 语法	简单描述
`$`	根节点
`@`	当前节点
`.or[]`	子节点
`..`	选择所有符合条件的节点
`*`	所有节点
`[]`	迭代器标示，如数组下标
`[,]`	支持迭代器中做多选
`[start:end]`	数组切片运算符
`?()`	支持过滤操作
`()`	支持表达式计算

例子

json 数据

{
    "store": {
        "book": [
            {
                "category": "reference",
                "author": "Nigel Rees",
                "title": "Sayings of the Century",
                "price": 8.95
            },
            {
                "category": "fiction",
                "author": "Evelyn Waugh",
                "title": "Sword of Honour",
                "price": 12.99
            },
            {
                "category": "fiction",
                "author": "Herman Melville",
                "title": "Moby Dick",
                "isbn": "0-553-21311-3",
                "price": 8.99
            },
            {
                "category": "fiction",
                "author": "J. R. R. Tolkien",
                "title": "The Lord of the Rings",
                "isbn": "0-395-19395-8",
                "price": 22.99
            }
        ],
        "bicycle": {
            "color": "red",
            "author":"DC-bicycle",
            "price": 19.95
        }
    },
    "expensive": 10,
    "author":"DC-store",
    "price": 33.33
}

以上面 json 数据为例，说明 JsonPath 语法使用：

JsonPath 表达式	描述
`$.store.book[*].author`	`store.book`节点下所有的`author`值
`$..author`	所有的 `author` 值
`$.store.*`	`store`节点下所有的值，包括`book`、`bicycle`
`$.store..price`	`store`节点下所有的`price`值
`$..book[2]`	第三个`book`
`$..book[-2]`	倒数第二个`book`
`$..book[0,1]`	第一个、第二个`book`
`$..book[:2]`	下标0到2的`book`
`$..book[1:2]`	下标1到2的`book`
`$..book[-2:]`	最后2个`book`
`$..book[2:]`	下标2的`book`到最后
`$..book[?(@.isbn)]`	所有含有`isbn`的`book`
`$.store.book[?(@.price < 10)]`	在`store`节点下，`price`小于10的`book`
`$..book[?(@.price <= $['expensive'])]`	在`store`节点下，不是"expensive"的`book`
`$..book[?(@.author =~ /.*REES/i)]`	匹配正则表达式`/.*REES/i`的`book`
`$..*`	每个节点都输出一次
`$..book.length()`	`book`的数目

PS：以上 JsonPath 可在这里验证正确性