1.
Javascript like objects and JSON
processing in VBA
cJobject primer from Excel Liberation

2.
Excel Liberation for details
cJobject purpose
The Excel/VBA model is
optimized for 2 dimensions
(rows/columns) – or at best 3
(sheets/rows/columns)
{
"Flintstone Characters": {
"families": [
{
"family": {
"name": "FlintStone",
"wife": "Wilma",
"husband": "Fred",
"kids": [
"Pebbles"
],
"pets": [
"Baby Puss",
"Dino",
"Doozy"
]
}
},
{
"family": {
"name": "Rubble",
"wife": "Betty",
"husband": "Barney",
"kids": [
"Bam Bam"
],
"pets": [
"Hoppy"
]
}
}
]
}
}
Data from web sources can be
any depth. VBA lacked the
capability to deal with either
the format or the structure of
JSON data. cJobject provides
both the structure and data
handling capability

3.
Excel Liberation for details
Javascript object versus cJobject
VBA lacks the syntax to express such an object as
concisely as javascript,but a similar capability can be
achieved with cJobjectAction javaScript cJobject
New object var job = {}; Set job = new cJobect
Create from JSON var job = JSON.parse(str); Set job = JSONParse(str)
Add a property job["Flintstone Characters”] = null; job.add ("Flintstone Characters”)
Add an array var f = job["Flintstone Characters”]
={families:[]};
Set f = job.child("Flintstone
Characters").add("families").addArr
ay
Add an array element
object
f.push({family:{name:”Flintstone”,wi
fe:”Wilma”,husband:”Fred”});
With f.add.add("family")
.add "name", "FlintStone"
.add "wife", "Wilma"
.add "husband", "Fred“
End with
Convert to JSON JSON.stringify(job); JSONstringify(job)
..or..
job.stringify()

4.
Excel Liberation for details
Portability
The Google Apps Script version of cJobject has the same
syntax (allowing for minor javaScript/VBA linguistic
differences)
Examples – Google Apps Script
var job = new cJobject();
job.add ("Flintstone Characters”);
var f = job.child("Flintstone Characters").add("families").addArray();
The cJobject is not really needed in GAS, since js can do
this natively. But using cJobject in GAS allows portability
to and from VBA. There are also native conversions for
GAS available
Examples – Google Apps Script
var job = fromNative(someObject);
var someObject = job.toNative();

5.
Excel Liberation for details
Iteration
How to iterate through cJobject children.
Examples - vba
for each joc in job.children
Debug.Print job.key,job.value
next joc
Examples - gas
job.children().forEach( function (joc) {
Logger.log (job.key() + “,” + job.value());
});
Equivalent in native javaScript
Examples
var jsObject = job.toNative();
for (k in jsObject ) {
console.log(k + “,” + jsObject [k]);
}

6.
Excel Liberation for details
Recursion
Since cJobjects are of inderminate depth, recursion is used internally in the
class and they are ideally suited for recursive usage. Here‟s an example of
traversing and printing an entire object tree irrespective of the data structure.
Examples
Public Function printFlint(Optional job As cJobject = Nothing, _
Optional depth As Long = 0)
Dim joc As cJobject
If (job Is Nothing) Then Set job = getFlintsoneCharacters()
Debug.Print Space(depth); job.key; ":"; job.value
depth = depth + 2
For Each joc In job.children
depth = printFlint(joc, depth)
Next joc
printFlint = depth - 2
End Function
Flintstone Characters:
families:
1:
family:
name:FlintStone
wife:Wilma
husband:Fred
kids:
1:Pebbles
pets:
saber tooth tiger:Baby Puss
dinosaur type dog thing:Dino
dodo bird:Doozy
2:
family:
name:Rubble
wife:Betty
husband:Barney
kids:
1:Bam Bam
pets:
kangaroo type thing:Hoppy

7.
Excel Liberation for details
Extensibility
Easy to extend with powerful capabilities
Examples
Populate a data set with JSON data
dSet.populateJSON jobject, Range("json1!$a$1")
Read a worksheet into a dset and convert it to JSON
dSet.populateData( Range("jSon2!$a$1"), , , , , , True).jObject.stringify()
Get the fullkey of any item
job.fullKey() – eg Flintstones characters.1.family.name
Find a property somewhere
set wilma = job.find(“Wilma”)
Make a treeview from a cJobject contents to display on a form
set t= job. toTreeView(treeViewObject)
Access data returned from a rest API query
With restQuery(worksheetName, "my society", , "postcode", _
, , , False, False)
For Each job In .jObject.children ......

8.
Excel Liberation for details
Chaining
The cJobect is designed to be chainable
Examples – VBA
With .add.add("module")
.add "name", module.name
.add "kind", module.textKind
With .add("procedures").addArray
For Each procedure In module.procedures
With .add.add("procedure")
.add "name", procedure.name
.add "scope", procedure.scope
.add "kind", procedure.procTextKind
.add "returns", procedure.procReturns
.add "lineCount", procedure.lineCount
.add "declaration", procedure.declaration
With .add("arguments").addArray
For Each argument In procedure.arguments
With .add.add("argument")
.add "name", argument.name
.add "optional", argument.isOptional
.add "default", argument.default
.add "argtype", argument.argType
End With
Next argument
End With
End With
Next procedure
End With
End With

9.
Excel Liberation for details
Custom classes and sub classes
Creating classes in VBA requires preknowledge about the class and its properties. The cJobject can
be used to create classes „on the fly‟ to avoid cluttering the source code with many small classes
Examples
With job.init(Nothing, "Flintstone Characters").add("families").addArray
With .add.add("family")
.add "name", "FlintStone"
.add "wife", "Wilma"
.add "husband", "Fred"
With .add("kids").addArray
.add , "Pebbles"
End With
With .add("pets").addArray
.add "saber tooth tiger", "Baby Puss"
.add "dinosaur type dog thing", "Dino"
.add "dodo bird", "Doozy"
End With
End With
End with
Set clone = job.clone()

10.
Excel Liberation for details
‘Javascript like’ optional arguments
It‟s very useful in javascript to be able to pass a single argument to a function containing options and
other data. The cJobject allows you do the something similar in VBA
Examples
.. Calling with a couple of non default options
reshapeMelt "{'outputSheet':'meltOut','id':['id','time']}“
-------------
Public Function rOptionDefaults() As String
„ the default options..
rOptionDefaults = _
"{'complain':true, 'inputSheet':'" & ActiveSheet.name & "'," & _
"'variableColumn' : 'variable', 'valueColumn' : 'value', 'id':['id'] ," & _
"'outputSheet': 'rOutputData' , 'clearContents':true}"
End Function
Public Function reshapeMelt(options As String) As cDataSet
„... Applies default options and meges with given options
Set jArgs = optionsExtend(options, rOptionDefaults)
' use the options...
With jArgs
If .toString("inputsheet") = .toString("outputsheet") Then
MsgBox ("Reading and writing to the same sheet - not allowed")
Exit Function
End If
End With

11.
Excel Liberation for details
Memory recovery
Like many objects with recursive linking, memory will
not be recovered by the VBA garbage collector
simply by going out of scope. A teardown is
provided, and should be used for efficient memory
recovery.
Examples
With JSONparse(str)
for each joc in .children
Debug.Print joc.value
next joc
.teardown
End With

12.
Excel Liberation for details
Summary
These examples show some of the capabilities of
cJObect and bringing a JSON capability to Excel
For more detail, and to download see Excel Liberation