C++

Modify Parts of JSON Document

See more JSON Examples

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
}

C++

#include <CkJsonObject.h>
#include <CkJsonArray.h>

void ChilkatSample(void)
    {
    bool success = false;

    CkJsonObject json;

    // Load the JSON from a file.
    success = json.LoadFile("qa_data/json/modifySample.json");
    if (success == false) {
        std::cout << json.lastErrorText() << "\r\n";
        return;
    }

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

    // Get the "list" array:

    CkJsonArray listA;

    json.ArrayOf2("list",listA);

    // Modify values in the list.

    // Change banana to plantain
    success = listA.SetStringAt(0,"plantain");

    // Change 12 to 24
    success = listA.SetIntAt(1,24);

    // Change true to false
    success = listA.SetBoolAt(2,false);

    // Is the 3rd item null?
    bool bNull = listA.IsNullAt(3);

    // Change "orange" to 32.
    success = listA.SetIntAt(4,32);

    // Change 12.5 to 31.2
    success = listA.SetNumberAt(5,"31.2");

    // Replace the { "ticker" : "AAPL" } object with { "ticker" : "GOOG" }
    // Do this by deleting, then inserting a new object at the same location.
    success = listA.DeleteAt(6);
    CkJsonObject tickerObj;
    listA.AddObjectAt2(6,tickerObj);

    success = tickerObj.AppendString("ticker","GOOG");

    // Replace "[ 1, 2, 3, 4, 5 ]" with "[ "apple", 22, true, null, 1080.25 ]"
    success = listA.DeleteAt(7);
    CkJsonArray aa;
    listA.AddArrayAt2(7,aa);

    success = aa.AddStringAt(-1,"apple");
    success = aa.AddIntAt(-1,22);
    success = aa.AddBoolAt(-1,true);
    success = aa.AddNullAt(-1);
    success = aa.AddNumberAt(-1,"1080.25");

    // Get the "fruit" array
    CkJsonArray aFruit;
    json.ArrayAt2(0,aFruit);

    // Get the 1st element:
    CkJsonObject appleObj;
    aFruit.ObjectAt2(0,appleObj);

    // Modify values by member name:
    success = appleObj.SetStringOf("fruit","fuji_apple");
    success = appleObj.SetIntOf("count",46);
    success = appleObj.SetBoolOf("fresh",false);
    success = appleObj.SetStringOf("extraInfo","developed by growers at the Tohoku Research Station in Fujisaki");

    // Modify values by index:

    CkJsonObject pearObj;
    aFruit.ObjectAt2(1,pearObj);

    success = pearObj.SetStringAt(0,"bartlett_pear");
    success = pearObj.SetIntAt(1,12);
    success = pearObj.SetBoolAt(2,false);
    success = pearObj.SetStringAt(3,"harvested in late August to early September");

    json.put_EmitCompact(false);
    std::cout << json.emit() << "\r\n";
    }