excel vba json parser
'-----------------------------------------------------------------------------------
' VBA JSON Parser
'-----------------------------------------------------------------------------------
Option Explicit
Private p&, token, dic
Function ParseJSON(json$, Optional key$ = "obj") As Object
p = 1
token = Tokenize(json)
Set dic = CreateObject("Scripting.Dictionary")
If token(p) = "{" Then ParseObj key Else ParseArr key
Set ParseJSON = dic
End Function
Function ParseObj(key$)
Do: p = p + 1
Select Case token(p)
Case "]"
Case "[": ParseArr key
Case "{"
If token(p + 1) = "}" Then
p = p + 1
dic.Add key, "null"
Else
ParseObj key
End If
Case "}": key = ReducePath(key): Exit Do
Case ":": key = key & "." & token(p - 1)
Case ",": key = ReducePath(key)
Case Else: If token(p + 1) <> ":" Then dic.Add key, token(p)
End Select
Loop
End Function
Function ParseArr(key$)
Dim e&
Do: p = p + 1
Select Case token(p)
Case "}"
Case "{": ParseObj key & ArrayID(e)
Case "[": ParseArr key
Case "]": Exit Do
Case ":": key = key & ArrayID(e)
Case ",": e = e + 1
Case Else: dic.Add key & ArrayID(e), token(p)
End Select
Loop
End Function
'-----------------------------------------------------------------------------------
' Support Functions
'-----------------------------------------------------------------------------------
Function Tokenize(s$)
Const Pattern = """(([^""\]|\.)*)""|[+-]?(?:0|[1-9]d*)(?:.d*)?(?:[eE][+-]?d+)?|w+|[^s""']+?"
Tokenize = RExtract(s, Pattern, True)
End Function
Function RExtract(s$, Pattern, Optional bGroup1Bias As Boolean, Optional bGlobal As Boolean = True)
Dim c&, m, n, v
With CreateObject("vbscript.regexp")
.Global = bGlobal
.MultiLine = False
.IgnoreCase = True
.Pattern = Pattern
If .TEST(s) Then
Set m = .Execute(s)
ReDim v(1 To m.Count)
For Each n In m
c = c + 1
v(c) = n.value
If bGroup1Bias Then If Len(n.submatches(0)) Or n.value = """""" Then v(c) = n.submatches(0)
Next
End If
End With
RExtract = v
End Function
Function ArrayID$(e)
ArrayID = "(" & e & ")"
End Function
Function ReducePath$(key$)
If InStr(key, ".") Then ReducePath = Left(key, InStrRev(key, ".") - 1)
End Function
