(Tcl) JSON: Array of Objects

Here we have a JSON object that contains an array, where each element in the array is a JSON object. This example demonstrates how to access the objects contained within an array.

{ 
  "employees":[
    {"firstName":"John", "lastName":"Doe"},
    {"firstName":"Anna", "lastName":"Smith"},
    {"firstName":"Peter","lastName":"Jones"}
  ]
}

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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 "{\"employees\":[{\"firstName\":\"John\", \"lastName\":\"Doe\"},{\"firstName\":\"Anna\", \"lastName\":\"Smith\"},{\"firstName\":\"Peter\",\"lastName\":\"Jones\"}]}"

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

# Get the "employees" array.
# employees is a CkJsonArray
set employees [CkJsonObject_ArrayOf $json "employees"]
if {[CkJsonObject_get_LastMethodSuccess $json] == 0} then {
    puts "employees member not found."
    delete_CkJsonObject $json
    exit
}

# Iterate over each employee, getting the JSON object at each index.
set numEmployees [CkJsonArray_get_Size $employees]
set i 0
while {$i < $numEmployees} {

    # empObj is a CkJsonObject
    set empObj [CkJsonArray_ObjectAt $employees $i]

    puts "{employee[}$i] = [CkJsonObject_stringOf $empObj firstName] [CkJsonObject_stringOf $empObj lastName]"
    delete_CkJsonObject $empObj

    set i [expr $i + 1]
}

delete_CkJsonArray $employees


delete_CkJsonObject $json