Lianja

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. Lianja

llSuccess = .F.

loJson = createobject("CkJsonObject")

// First build simple JSON..
loJson.UpdateInt("test.abc",100)

loJson.EmitCompact = .F.
? loJson.Emit()

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

lcPath = "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?
lnVal = loJson.IntOf(lcPath)
? "val = " + str(lnVal)

// 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 .T. = success and .F. = 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..
llWasFound = loJson.LastMethodSuccess
? "wasFound = " + str(llWasFound) + " (not a valid indicator)"

// Instead, if the returned value is 0, we can double-check to see if the member was truly there..
if (lnVal = 0) then
    llWasFound = loJson.HasMember(lcPath)
    ? "wasFound = " + str(llWasFound)
    if (llWasFound = .T.) then
        ? "The value was present and is 0."
    else
        ? "no member is present at test.notHere"
    endif

else
    ? "val = " + str(lnVal)
endif

// Alternatively, you could check to see if the member exists beforehand..
if (loJson.HasMember(lcPath) = .T.) then
    ? "val = " + str(loJson.IntOf(lcPath))
else
    ? "no member at " + lcPath
endif



release loJson