C

Check if Integer Exists at JSON Path

Demonstrates how to get an integer value at a JSON path, and how to check to see if it exists. C

#include <C_CkJsonObject.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkJsonObject json;
    const char *path;
    int val;
    BOOL wasFound;

    success = FALSE;

    json = CkJsonObject_Create();

    //  First build simple JSON..
    CkJsonObject_UpdateInt(json,"test.abc",100);

    CkJsonObject_putEmitCompact(json,FALSE);
    printf("%s\n",CkJsonObject_emit(json));

    //  This is our JSON:
    //  {
    //    "test": {
    //      "abc": 100,
    //    }
    //  }

    path = "test.notHere";

    //  The call to IntOf will return 0, because it's not present.
    //  But how do we know if it really was present, and the value was truly 0?
    val = CkJsonObject_IntOf(json,path);
    printf("val = %d\n",val);

    //  We cannot use LastMethodSuccess because LastMethodSuccess only applies
    //  to methods that:
    //  - return a string
    //  - return a new Chilkat object, binary bytes, or a date/time.
    //  - returns a boolean status where TRUE = success and FALSE = failed.
    //  - returns an integer where failure is defined by a return value less than zero.
    //  The IntOf method fits none of these requirements, and therefore the LastMethodSuccess 
    //  is not a valid indicator..
    wasFound = CkJsonObject_getLastMethodSuccess(json);
    printf("wasFound = %d (not a valid indicator)\n",wasFound);

    //  Instead, if the returned value is 0, we can double-check to see if the member was truly there..
    if (val == 0) {
        wasFound = CkJsonObject_HasMember(json,path);
        printf("wasFound = %d\n",wasFound);
        if (wasFound == TRUE) {
            printf("The value was present and is 0.\n");
        }
        else {
            printf("no member is present at test.notHere\n");
        }

    }
    else {
        printf("val = %d\n",val);
    }

    //  Alternatively, you could check to see if the member exists beforehand..
    if (CkJsonObject_HasMember(json,path) == TRUE) {
        printf("val = %d\n",CkJsonObject_IntOf(json,path));
    }
    else {
        printf("no member at %s\n",path);
    }



    CkJsonObject_Dispose(json);

    }