(Excel) Read/Write JSON with Binary Data such as JPEG Files

Demonstrates how binary files could be stored in JSON in base64 format. Creates JSON containing the contents of a JPG file, and then reads the JSON to extract the JPEG image.

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' First load a small JPG file..
Dim bd As Chilkat.BinData
Set bd = Chilkat.NewBinData


success = bd.LoadFile("qa_data/jpg/starfish20.jpg")
' Assume success, but your code should check for success..

' Create JSON containing the binary data in base64 format.
Dim json1 As Chilkat.JsonObject
Set json1 = Chilkat.NewJsonObject
Dim success As Boolean
success = json1.UpdateBd("starfish","base64",bd)


jsonStr = json1.Emit()
Debug.Print jsonStr

' Here's the output:
' {"starfish":"/9j/4AAQSkZJRgA ... cN2iuLFsCEbDGxQkI6RO/n//2Q=="}

' Let's create a new JSON object, load it with the above JSON, and extract the JPG image..
Dim json2 As Chilkat.JsonObject
Set json2 = Chilkat.NewJsonObject
success = json2.Load(jsonStr)

' Get the binary bytes.
Dim bd2 As Chilkat.BinData
Set bd2 = Chilkat.NewBinData
success = json2.BytesOf("starfish","base64",bd2)

' Save to a file.
success = bd2.WriteFile("qa_output/starfish20.jpg")

Debug.Print "Success."