(C) Get the Root of a JSON Document

Demonstrates how to get back to the JSON root object from anywhere in the JSON document. This example uses the following JSON document:

{
  "flower": "tulip",
  "abc":
    {
    "x": [
       { "a" : 1 },
       { "b1" : 100, "b2" : 200 },
       { "c" : 3 }
    ],
    "y": 200,
    "z": 200
    }
}

Note: This example requires Chilkat v11.0.0 or greater.

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#include <C_CkJsonObject.h>
#include <C_CkJsonArray.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkJsonObject json;
    const char *jsonStr;
    HCkJsonObject abcObj;
    HCkJsonArray xArray;
    HCkJsonObject bObj;
    HCkJsonObject docRoot;

    success = FALSE;

    json = CkJsonObject_Create();

    jsonStr = "{\"flower\": \"tulip\",\"abc\":{\"x\": [{ \"a\" : 1 },{ \"b1\" : 100, \"b2\" : 200 },{ \"c\" : 3 }],\"y\": 200,\"z\": 200}}";

    success = CkJsonObject_Load(json,jsonStr);
    if (success == FALSE) {
        printf("%s\n",CkJsonObject_lastErrorText(json));
        CkJsonObject_Dispose(json);
        return;
    }

    // Get the "abc" object.
    abcObj = CkJsonObject_Create();
    success = CkJsonObject_ObjectOf2(json,"abc",abcObj);
    if (success == FALSE) {
        printf("%s\n",CkJsonObject_lastErrorText(json));
        CkJsonObject_Dispose(json);
        CkJsonObject_Dispose(abcObj);
        return;
    }

    // Side note: The JSON of a sub-part of the document can be emitted from any JSON object:
    CkJsonObject_putEmitCompact(abcObj,FALSE);
    printf("%s\n",CkJsonObject_emit(abcObj));

    // Navigate to the "x" array
    xArray = CkJsonArray_Create();
    CkJsonObject_ArrayOf2(abcObj,"x",xArray);

    // Navigate to the 2nd object contained within the array.  This contains members b1 and b2
    bObj = CkJsonObject_Create();
    CkJsonArray_ObjectAt2(xArray,1,bObj);

    // Show that we're at "b1/b2".
    // The value of "b1" should be "200"
    printf("b2 = %d\n",CkJsonObject_IntOf(bObj,"b2"));

    // Now go back to the JSON doc root:
    docRoot = CkJsonObject_Create();
    CkJsonObject_GetDocRoot2(bObj,docRoot);

    // We'll skip the null check and assume it's non-null...

    // Pretty-print the JSON doc from the root to show that this is indeed the root.
    CkJsonObject_putEmitCompact(docRoot,FALSE);
    printf("%s\n",CkJsonObject_emit(docRoot));


    CkJsonObject_Dispose(json);
    CkJsonObject_Dispose(abcObj);
    CkJsonArray_Dispose(xArray);
    CkJsonObject_Dispose(bObj);
    CkJsonObject_Dispose(docRoot);

    }