Visual Basic 6.0

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. Visual Basic 6.0

Dim success As Long
success = 0

Dim json As New ChilkatJsonObject

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

json.EmitCompact = 0
Debug.Print 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 Long
val = json.IntOf(path)
Debug.Print "val = " & 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 1 = success and 0 = 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 Long
wasFound = json.LastMethodSuccess
Debug.Print "wasFound = " & 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)
    Debug.Print "wasFound = " & wasFound
    If (wasFound = 1) Then
        Debug.Print "The value was present and is 0."
    Else
        Debug.Print "no member is present at test.notHere"
    End If

Else
    Debug.Print "val = " & val
End If

' Alternatively, you could check to see if the member exists beforehand..
If (json.HasMember(path) = 1) Then
    Debug.Print "val = " & json.IntOf(path)
Else
    Debug.Print "no member at " & path
End If