B4J Code Snippet Recursive Tree Parsing - simple example

Hi

The json tree source code inspires this example.

1. You have a map object with a "children" key.
2. This "children" key holds a list of items, which can also have other "children" keys.
3. This returns a list of all items where each child has an "attributes" key

Usage:

Dim treeSchema As List
Dim tree As Map = CreateMap("children": ...)
treeSchema = ParseTree(tree)

Snippet

Sub ParseTree(root As Map)
    'does this contains children
    If root.ContainsKey("children") Then
        'get the children
        Dim children As List = root.Get("children")
        'loop through each child
        For Each child As Map In children
            'create a new record
            Dim nitem As Map = CreateMap()
            'get some prop
            Dim tagName As String = child.GetDefault("tagName", "")
            Dim parentID As String = root.GetDefault("id", "")
            'update new record
            nitem.Put("tagname", tagName)
            nitem.Put("parent", parentID)
            'does this child have attributes
            If child.ContainsKey("attributes") = False Then Continue
            'get the attributes
            Dim attrs As Map = child.get("attributes")
            For Each attr As String In attrs.Keys
                Dim attrv As String = attrs.Get(attr)
                nitem.Put(attr, attrv)
            Next
            treeSchema.Add(nitem)
            ParseTree(child)
        Next
    End If
End Sub