VBA-FastJSON

Fast Native JSON Parser / Serializer for VBA. Compatible with Windows and Mac.

RFC 8259 compliant.

This Parser / Serializer is intended for VBA. However, it is compatible with VBA7 / twinBASIC / VB6 / VBA6.

Installation

Download the latest release, extract and import the LibJSON.bas module into your project.

Additionally, a Dictionary is required. While you can use Scripting.Dictionary (Microsoft Scripting Runtime reference - scrrun.dll on Windows), it is recommended to use VBA-FastDictionary because:

• is Mac compatible
• is faster in almost every way - see Benchmarking VBA-FastDictionary
• allows endless nesting
• will still work if Scripting.Dictionary becomes obsolete

For more information see Cons of Scripting.Dictionary

Parser

For more details see Parser documentation.

Parse method:

• RFC 8259 compliant
• memory-efficient, non-recursive implementation - avoids 'Out of stack space' for deep nesting
• fast, for a native implementation
• automatic encoding detection and conversion. Supports: UTF8, UTF16LE, UTF16BE, UTF32LE, UTF32BE
• various extensions via the available parameters - see Parser extensions
• json input can be a String or a one-dimensional array of Byte() or Integer() type
• input is parsed in place without making any copies
• does not throw errors

Serializer

For more details see Serializer documentation.

Serialize method:

• memory-efficient, non-recursive implementation - avoids 'Out of stack space' for deep nesting
• fast, for a native implementation
• supports beautify / minify via the indentSpaces argument
• by default, cannot fail - see available options via the function parameters
• returns a String data type
• detects circular object references
• can sort keys
• supports multi-dimensional arrays, row-wise
• supports encoding: UTF8, UTF16LE (default), UTF16BE, UTF32LE, UTF32BE
• does not throw errors

Testing

Download the latest release, extract and import the TestLibJSON.bas module into your project. Run RunAllJSONTests method. On failure, execution will stop on the first failed Assert.

Many thanks to Nicolas Seriot (@nst). This repo includes some of the tests found at JSONTestSuite. A must-read, see his article: Parsing JSON is a Minefield!

Demo

Debug.Print Parse("{""key"":[1,2,3,4,5,true]}").Value("key")(6) 'True
'
Debug.Print Parse("[[[[[]]]]]", maxNestingDepth:=4).Error 'Max Depth Hit at char position 5
'
Debug.Print Parse("    false").Value 'False
'
Debug.Print Parse(ChrW$(&HBBEF) & ChrB$(&HBF) & "{}", failIfBOMDetected:=True).IsValid 'False
Debug.Print Parse(ChrW$(&HBBEF) & ChrB$(&HBF) & "{}").Value.Count '0
'
Debug.Print Parse("0E0").Value '0
'
Dim res As Variant
Dim jsonText() As Byte: ReadBytes "myFilePath", jsonText
'
With Parse(jsonText, jpCodeUTF8)
    If .IsValid Then
        If IsObject(.Value) Then Set res = .Value Else res = .Value
    Else
        MsgBox .Error
        Exit Sub
    End If
End With
'
Dim jsonData As New Dictionary
Dim json As String
'
jsonData.Add "d", 1
jsonData.Add 7, 2
jsonData.Add "a", 3
jsonData.Add "b", 4
'
json = Serialize(jsonData)                                        '{"d":1,"a":3,"b":4}
json = Serialize(jsonData, sortKeys:=True)                        '{"a":3,"b":4,"d":1}
json = Serialize(jsonData, sortKeys:=True, forceKeysToText:=True) '{"7":2,"a":3,"b":4,"d":1}
'
json = Serialize(jsonData, indentSpaces:=2)                       '{
                                                                  '  "d": 1,
                                                                  '  "a": 3,
                                                                  '  "b": 4
                                                                  '}
json = Serialize(jsonData, jpCode:=jpCodeUTF8)