how can i get length of array attribute

[biexiang]

how can i get length of array attribute, just like the code:
{ "name": "John", "age": 31, "city": "New York", "ls": [ { "name": "John2", "age": "23" }, { "name": "John3", "age": "24" } ] }
how can i get size of ls

[buger]

Implemented in v1.4.0 — GetArrayLen(data, "ls") returns the array length in a single pass. See: https://github.com/buger/jsonparser/releases/tag/v1.4.0