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.
####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
```lua
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.
####Syntax
`cjson.decode(str)`
####Parameters
`str` JSON string to decode
####Returns
Lua table representation of the JSON data
####Example
```lua
t = cjson.decode('{"key":"value"}')
for k,v in pairs(t) do print(k,v) end
```