(Xojo Plugin) Get the Index of a JSON Member

This example demonstrates how to get the index of a given member by name.

{
  "name": "donut",
  "image":
    {
    "fname": "donut.jpg",
    "w": 200,
    "h": 200
    },
  "thumbnail":
    {
    "fname": "donutThumb.jpg",
    "w": 32,
    "h": 32
    }
}

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Dim json As New Chilkat.JsonObject

// This is the above JSON with whitespace chars removed (SPACE, TAB, CR, and LF chars).
// The presence of whitespace chars for pretty-printing makes no difference to the Load
// method. 
Dim jsonStr As String
jsonStr = "{""name"": ""donut"",""image"":{""fname"": ""donut.jpg"",""w"": 200,""h"": 200},""thumbnail"":{""fname"": ""donutThumb.jpg"",""w"": 32,""h"": 32}}"

Dim success As Boolean
success = json.Load(jsonStr)
If (success <> True) Then
    System.DebugLog(json.LastErrorText)
    Return
End If

// The top-level JSON object has three members: name, image, and thumbnail.
Dim nameIndex As Int32
nameIndex = json.IndexOf("name")
// The index of the "name" member is 0.
System.DebugLog("nameIndex = " + Str(nameIndex))

Dim thumbIndex As Int32
thumbIndex = json.IndexOf("thumbnail")
// The index of the "thumbnail" member is 2.
System.DebugLog("thumbIndex = " + Str(thumbIndex))

// The "fname" member is NOT a direct member of the top-level JSON object.
// It is a member of a nested object.  If we try to get the index of this
// member using the top-level JSON object, it is not found (and returns -1).
Dim fnameIndex As Int32
fnameIndex = json.IndexOf("fname")
// The fnameIndex is -1 (not found).  This is correct.
System.DebugLog("fnameIndex = " + Str(fnameIndex))

// Get the "image" object.
Dim imageObj As Chilkat.JsonObject
imageObj = json.ObjectOf("image")
If (json.LastMethodSuccess = False) Then
    System.DebugLog("image object not found.")
    Return
End If

// Now we can get the index of the "fname" object, because it is a direct
// member of the "image" object:
fnameIndex = imageObj.IndexOf("fname")
System.DebugLog("fnameIndex = " + Str(fnameIndex))