Upload a file via wininet with a POST

Hi Team,

we are using the Dropbox REST API with OAuth2.
When attempting to upload a file I don't know where to put the file contents using the wininet for http way.

 

In the docs there is just a curl example

curl -X POST https://content.dropboxapi.com/2/files/upload \
    --header "Authorization: Bearer 

" \
    --header "Dropbox-API-Arg: {\"path\": \"/Homework/math/Matrices.txt\",\"mode\": \"add\",\"autorename\": true,\"mute\": false}" \
    --header "Content-Type: application/octet-stream" \
    --data-binary @local_file.txt

but I don't understand how to put the contents file.

I see the 3 headers like in the example but what about the file ?.

data-binary is put in the body ?

or in the header ?

and how ?

I used the postman tool to reproduce the upload I was successful. The problem is that the postman put the file in the body in a binary way selecting the file with a explorer but I cannot see how and where to put it using HttpSendRequest with a POST verb.

 

Any suggestion to do it ?

Thanks in advance