Xojo Plugin

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. Xojo Plugin

Dim success As Boolean
success = False

Dim json As New Chilkat.JsonObject

// First build simple JSON..
success = json.UpdateInt("test.abc",100)

json.EmitCompact = False
System.DebugLog(json.Emit())

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

Dim path As String
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?
Dim val As Int32
val = json.IntOf(path)
System.DebugLog("val = " + Str(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..
Dim wasFound As Boolean
wasFound = json.LastMethodSuccess
System.DebugLog("wasFound = " + Str(wasFound) + " (not a valid indicator)")

// Instead, if the returned value is 0, we can double-check to see if the member was truly there..
If (val = 0) Then
    wasFound = json.HasMember(path)
    System.DebugLog("wasFound = " + Str(wasFound))
    If (wasFound = True) Then
        System.DebugLog("The value was present and is 0.")
    Else
        System.DebugLog("no member is present at test.notHere")
    End If

Else
    System.DebugLog("val = " + Str(val))
End If

// Alternatively, you could check to see if the member exists beforehand..
If (json.HasMember(path) = True) Then
    System.DebugLog("val = " + Str(json.IntOf(path)))
Else
    System.DebugLog("no member at " + path)
End If