Parse and access deepl.com API response with VBA - vba

Question

I have a VBA function which retrieves data from the deepl.com API (translation).
Private Function Translate_Text(INPUT_TEXT As String) As String
Dim apiKey As String
Dim textToTranslate As String
Dim fromLanguage As String
Dim toLanguage As String
Dim request As New MSXML2.XMLHTTP60
Dim response As New MSHTML.HTMLDocument
' Set my API key here
apiKey = myAPIKey
' Get the text to translate from a text box
textToTranslate = INPUT_TEXT
' Set the languages to translate from and to
fromLanguage = "en"
toLanguage = "de"
' Send the request to the DeepL API
request.Open "POST", "https://api-free.deepl.com/v2/translate?", False
request.SetRequestHeader "Content-Type", "application/x-www-form-urlencoded"
request.Send "auth_key=" & apiKey & "&text=" & textToTranslate & "&source_lang=" & fromLanguage & "&target_lang=" & toLanguage
' Parse the response from the API
response.body.innerHTML = request.responseText
Debug.Print request.responseText
This print shows that the request itself was successful:
{"translations":[{"detected_source_language":"EN","text":"Steigerung der Benutzereffizienz"}]}
I then try to access the "text" element:
translatedText = response.getElementsByTagName("text")(0).innerText
However this throws an error ("Object variable or with block variable not defined")
So my question is how I can correctly access the text in the response object.

Answer 1

The request you get from the API is JSON formatted, not HTML.
You can not use getElementsByTagName on JSON that's why it always says its empty.
You would need to use something like VBA-JSON (as suggested by Tim Williams above). https://github.com/VBA-tools/VBA-JSON
When using VBA-JSON you can do something like this:
Dim Json As Object
Set Json = JsonConverter.ParseJson(request.responseText)
Debug.Print Json.text