nodemcu-firmware/docs/en/modules/cjson.md

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CJSON Module

The JSON support module. Allows encoding and decoding to/from JSON.

Please note that nested tables can require a lot of memory to encode. To catch out-of-memory errors, use pcall().

cjson.encode()

Encode a Lua table to a JSON string. For details see the documentation of the original Lua library.

####Syntax cjson.encode(table)

####Parameters table data to encode

While it also is possible to encode plain strings and numbers rather than a table, it is not particularly useful to do so.

####Returns JSON string

####Example

ok, json = pcall(cjson.encode, {key="value"})
if ok then
  print(json)
else
  print("failed to encode!")
end

cjson.decode()

Decode a JSON string to a Lua table. For details see the documentation of the original Lua library.

####Syntax cjson.decode(str)

####Parameters str JSON string to decode

####Returns Lua table representation of the JSON data

####Example

t = cjson.decode('{"key":"value"}')
for k,v in pairs(t) do print(k,v) end