(Tcl) JSON: Nested Objects

Here we have a JSON object that contains nested JSON objects. This example demonstrates how to access the contents of the nested objects.

{
  "name": "donut",
  "image":
    {
    "fname": "donut.jpg",
    "w": 200,
    "h": 200
    },
  "thumbnail":
    {
    "fname": "donutThumb.jpg",
    "w": 32,
    "h": 32
    }
}

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load ./chilkat.dll

set json [new_CkJsonObject]

# This is the above JSON with whitespace chars removed (SPACE, TAB, CR, and LF chars).
# The presence of whitespace chars for pretty-printing makes no difference to the Load
# method. 
set jsonStr "{\"name\": \"donut\",\"image\":{\"fname\": \"donut.jpg\",\"w\": 200,\"h\": 200},\"thumbnail\":{\"fname\": \"donutThumb.jpg\",\"w\": 32,\"h\": 32}}"

set success [CkJsonObject_Load $json $jsonStr]
if {$success != 1} then {
    puts [CkJsonObject_lastErrorText $json]
    delete_CkJsonObject $json
    exit
}

# Get the "image" object.
# imageObj is a CkJsonObject
set imageObj [CkJsonObject_ObjectOf $json "image"]
if {[CkJsonObject_get_LastMethodSuccess $json] == 0} then {
    puts "image object not found."
    delete_CkJsonObject $json
    exit
}

puts "image: fname=[CkJsonObject_stringOf $imageObj fname], width=[CkJsonObject_IntOf $imageObj w], height=[CkJsonObject_IntOf $imageObj h]"

delete_CkJsonObject $imageObj

# Get the "thumbnail" object.
# thumbObj is a CkJsonObject
set thumbObj [CkJsonObject_ObjectOf $json "thumbnail"]
if {[CkJsonObject_get_LastMethodSuccess $json] == 0} then {
    puts "thumbnail object not found."
    delete_CkJsonObject $json
    exit
}

puts "thumbnail: fname=[CkJsonObject_stringOf $thumbObj fname], width=[CkJsonObject_IntOf $thumbObj w], height=[CkJsonObject_IntOf $thumbObj h]"

delete_CkJsonObject $thumbObj


delete_CkJsonObject $json