Android™

Understanding JSON Array vs JSON Object

See more JSON Examples

This example explains the difference between a JSON Array and a JSON Object. A JSON Array begins with "[" and ends with "]", whereas a JSON Object begins with "{" and ends with "}".

Elements contained in a JSON array are accessed by index, whereas elements in a JSON object are typically accessed by name (but can also be accessed by index).

Android™

// Important: Don't forget to include the call to System.loadLibrary
// as shown at the bottom of this code sample.
package com.test;

import android.app.Activity;
import com.chilkatsoft.*;

import android.widget.TextView;
import android.os.Bundle;

public class SimpleActivity extends Activity {

  private static final String TAG = "Chilkat";

  // Called when the activity is first created.
  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    boolean success = false;

    // A JSON array should be loaded into a Chilkat JSON array,
    // whereas a JSON object should be loaded into a Chilkat JSON object.

    // A JSON array may contain objects, and a JSON object may contains arrays, but
    // it is the top-level (outermost) element that defines whether the JSON
    // document is an array or an object.
    // An array begins and ends with "[" ... "]"
    // An object begins and ends with "{" ... "}"

    // For example, an array containing 2 objects:
    String strJsonArray = "[ { \"name\": \"Bill\" }, { \"name\": \"Ted\" } ]";

    // Load it into a JSON array.
    CkJsonArray jsonA = new CkJsonArray();
    success = jsonA.Load(strJsonArray);
    Log.i(TAG, "number of array elements: " + String.valueOf(jsonA.get_Size()));

    // This is an object containing an array:
    String strJsonObj = "{ \"characters\": [ \"Bill\", \"Ted\" ] }";

    // Load it into a JSON object.
    CkJsonObject jsonO = new CkJsonObject();
    success = jsonO.Load(strJsonObj);
    Log.i(TAG, "number of object members: " + String.valueOf(jsonO.get_Size()));

  }

  static {
      System.loadLibrary("chilkat");

      // Note: If the incorrect library name is passed to System.loadLibrary,
      // then you will see the following error message at application startup:
      //"The application <your-application-name> has stopped unexpectedly. Please try again."
  }
}