Hello Team,
Is there any api to download files from folder(for example: test) having filename with prefix(say: log_) using javascript.
The Dropbox API doesn't offer a way to list/download files based on a particular prefix like this. You could use /2/files/list_folder[/continue] to list files and folders, filter the result to the desired files, and then download them using /2/files/download though.
Those are links to the documentation for the HTTPS endpoints themselves, but we recommend using one of the official SDKs if possible. Those have corresponding native methods for the HTTPS endpoints. For example, we do offer an official Dropbox API v2 JavaScript SDK. In that, the corresponding methods are: filesListFolder, filesListFolderContinue, and filesDownload.