(Tcl) Modify Parts of JSON Document

Demonstrates how to modify parts of a JSON document. This example uses the following JSON document:

{
   "fruit": [
      	{
         "kind": "apple",
	 "count": 24,
	 "fresh": true,
	 "extraInfo": null,
	 "listA": [ "abc", 1, null, false ],
	 "objectB": { "animal" : "monkey" }
      	},
	{
         "kind": "pear",
	 "count": 18,
	 "fresh": false,
	 "extraInfo": null
	 "listA": [ "xyz", 24, null, true ],
	 "objectB": { "animal" : "lemur" }
	}
    ],
    "list" : [ "banana", 12, true, null, "orange", 12.5, { "ticker": "AAPL" }, [ 1, 2, 3, 4, 5 ] ],
    "alien" : true
}

Chilkat Tcl Extension Downloads Chilkat Tcl Extension Downloads

load ./chilkat.dll

set json [new_CkJsonObject]

# Load the JSON from a file.
set success [CkJsonObject_LoadFile $json "qa_data/json/modifySample.json"]
if {$success != 1} then {
    puts [CkJsonObject_lastErrorText $json]
    delete_CkJsonObject $json
    exit
}

# This example will not check for errors (i.e. null / false / 0 return values)...

# Get the "list" array:
# listA is a CkJsonArray
set listA [CkJsonObject_ArrayOf $json "list"]

# Modify values in the list.

# Change banana to plantain
set success [CkJsonArray_SetStringAt $listA 0 "plantain"]

# Change 12 to 24
set success [CkJsonArray_SetIntAt $listA 1 24]

# Change true to false
set success [CkJsonArray_SetBoolAt $listA 2 0]

# Is the 3rd item null?
set bNull [CkJsonArray_IsNullAt $listA 3]

# Change "orange" to 32.
set success [CkJsonArray_SetIntAt $listA 4 32]

# Change 12.5 to 31.2
set success [CkJsonArray_SetNumberAt $listA 5 "31.2"]

# Replace the { "ticker" : "AAPL" } object with { "ticker" : "GOOG" }
# Do this by deleting, then inserting a new object at the same location.
set success [CkJsonArray_DeleteAt $listA 6]
set success [CkJsonArray_AddObjectAt $listA 6]
# tickerObj is a CkJsonObject
set tickerObj [CkJsonArray_ObjectAt $listA 6]
set success [CkJsonObject_AddStringAt $tickerObj -1 "ticker" "GOOG"]

delete_CkJsonObject $tickerObj

# Replace "[ 1, 2, 3, 4, 5 ]" with "[ "apple", 22, true, null, 1080.25 ]"
set success [CkJsonArray_DeleteAt $listA 7]
set success [CkJsonArray_AddArrayAt $listA 7]
# aa is a CkJsonArray
set aa [CkJsonArray_ArrayAt $listA 7]
set success [CkJsonArray_AddStringAt $aa -1 "apple"]
set success [CkJsonArray_AddIntAt $aa -1 22]
set success [CkJsonArray_AddBoolAt $aa -1 1]
set success [CkJsonArray_AddNullAt $aa -1]
set success [CkJsonArray_AddNumberAt $aa -1 "1080.25"]
delete_CkJsonArray $aa

delete_CkJsonArray $listA

# Get the "fruit" array
# aFruit is a CkJsonArray
set aFruit [CkJsonObject_ArrayAt $json 0]

# Get the 1st element:
# appleObj is a CkJsonObject
set appleObj [CkJsonArray_ObjectAt $aFruit 0]

# Modify values by member name:
set success [CkJsonObject_SetStringOf $appleObj "fruit" "fuji_apple"]
set success [CkJsonObject_SetIntOf $appleObj "count" 46]
set success [CkJsonObject_SetBoolOf $appleObj "fresh" 0]
set success [CkJsonObject_SetStringOf $appleObj "extraInfo" "developed by growers at the Tohoku Research Station in Fujisaki"]

delete_CkJsonObject $appleObj

# Modify values by index:
# pearObj is a CkJsonObject
set pearObj [CkJsonArray_ObjectAt $aFruit 1]
set success [CkJsonObject_SetStringAt $pearObj 0 "bartlett_pear"]
set success [CkJsonObject_SetIntAt $pearObj 1 12]
set success [CkJsonObject_SetBoolAt $pearObj 2 0]
set success [CkJsonObject_SetStringAt $pearObj 3 "harvested in late August to early September"]
delete_CkJsonObject $pearObj

delete_CkJsonArray $aFruit

CkJsonObject_put_EmitCompact $json 0
puts [CkJsonObject_emit $json]

delete_CkJsonObject $json