更新时间:2023-01-17 19:11:59
非常接近!在select
表达式中,必须在contains
之前使用管道(|
).
Very close! In your select
expression, you have to use a pipe (|
) before contains
.
此过滤器产生预期的输出.
This filter produces the expected output.
. - map(select(.Names[] | contains ("data"))) | .[] .Id
jq食谱给出了语法示例.
根据键的内容过滤对象
例如,我只想要流派键包含"house"的对象.
Filter objects based on the contents of a key
E.g., I only want objects whose genre key contains "house".
$ json='[{"genre":"deep house"}, {"genre": "progressive house"}, {"genre": "dubstep"}]'
$ echo "$json" | jq -c '.[] | select(.genre | contains("house"))'
{"genre":"deep house"}
{"genre":"progressive house"}
Colin D asks how to preserve the JSON structure of the array, so that the final output is a single JSON array rather than a stream of JSON objects.
最简单的方法是将整个表达式包装在数组构造函数中:
The simplest way is to wrap the whole expression in an array constructor:
$ echo "$json" | jq -c '[ .[] | select( .genre | contains("house")) ]'
[{"genre":"deep house"},{"genre":"progressive house"}]
您还可以使用地图功能:
You can also use the map function:
$ echo "$json" | jq -c 'map(select(.genre | contains("house")))'
[{"genre":"deep house"},{"genre":"progressive house"}]
map解压缩输入数组,将过滤器应用于每个元素,然后创建一个新数组.换句话说,map(f)
等同于[.[]|f]
.
map unpacks the input array, applies the filter to every element, and creates a new array. In other words, map(f)
is equivalent to [.[]|f]
.