Dart

JSON: Nested Array

See more JSON Examples

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

{
 "numbers" : [ 
    ["even", 2, 4, 6, 8], 
    ["prime", 2, 3, 5, 7, 11, 13] 
  ] }

Dart

import 'package:chilkat/chilkat.dart';

void main() {
  final json = 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. 
  final jsonStr = '{ "numbers" : [ ["even", 2, 4, 6, 8], ["prime", 2, 3, 5, 7, 11, 13] ] }';

  try {
    json.load(jsonStr);
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  // Get the value of the "numbers" object, which is an array that contains JSON arrays.
  final CkJsonArray outerArray;
  try {
    outerArray = json.arrayOf('numbers');
  } on ChilkatException {
    print('numbers array not found.');
    return;
  }

  final numArrays = outerArray.size;

  for (var i = 0; i < numArrays; i++) {

    final innerArray = outerArray.arrayAt(i);

    // The first item in the innerArray is a string
    print('${innerArray.stringAt(0)}:');

    final numInnerItems = innerArray.size;
    for (var j = 1; j < numInnerItems; j++) {

      print('  ${innerArray.intAt(j)}');
    }
  }
}