electron/docs/api/download-item.md

DownloadItem

Control file downloads from remote sources.

DownloadItem is an EventEmitter that represents a download item in Electron. It is used in will-download event of Session class, and allows users to control the download item.

// In the main process.
win.webContents.session.on('will-download', (event, item, webContents) => {
  // Set the save path, making Electron not to prompt a save dialog.
  item.setSavePath('/tmp/save.pdf')

  item.on('updated', (event, state) => {
    if (state === 'interrupted') {
      console.log('Download is interrupted but can be resumed')
    } else if (state === 'progressing') {
      if (item.isPaused()) {
        console.log('Download is paused')
      } else {
        console.log(`Received bytes: ${item.getReceivedBytes()}`)
      }
    }
  })
  item.once('done', (event, state) => {
    if (state === 'completed') {
      console.log('Download successfully')
    } else {
      console.log(`Download failed: ${state}`)
    }
  })
})

Events

Event: 'updated'

Returns:

• event Event
• state String

Emitted when the download has been updated and is not done.

The state can be one of following:

• progressing - The download is in-progress.
• interrupted - The download has interrupted and can be resumed.

Event: 'done'

Returns:

• event Event
• state String

Emitted when the download is in a terminal state. This includes a completed download, a cancelled download(via downloadItem.cancel()), and interrupted download that can't be resumed.

The state can be one of following:

• completed - The download completed successfully.
• cancelled - The download has been cancelled.
• interrupted - The download has interrupted and can not resume.

Methods

The downloadItem object has the following methods:

downloadItem.setSavePath(path)

• path String - Set the save file path of the download item.

The API is only available in session's will-download callback function. If user doesn't set the save path via the API, Electron will use the original routine to determine the save path(Usually prompts a save dialog).

downloadItem.pause()

Pauses the download.

downloadItem.isPaused()

Returns whether the download is paused.

downloadItem.resume()

Resumes the download that has been paused.

downloadItem.canResume()

Resumes whether the download can resume.

downloadItem.cancel()

Cancels the download operation.

downloadItem.getURL()

Returns a String represents the origin url where the item is downloaded from.

downloadItem.getMimeType()

Returns a String represents the mime type.

downloadItem.hasUserGesture()

Returns a Boolean indicates whether the download has user gesture.

downloadItem.getFilename()

Returns a String represents the file name of the download item.

Note: The file name is not always the same as the actual one saved in local disk. If user changes the file name in a prompted download saving dialog, the actual name of saved file will be different.

downloadItem.getTotalBytes()

Returns a Integer represents the total size in bytes of the download item. If the size is unknown, it returns 0.

downloadItem.getReceivedBytes()

Returns a Integer represents the received bytes of the download item.

downloadItem.getContentDisposition()

Returns a String represents the Content-Disposition field from the response header.

downloadItem.getState()

Returns current state as String.

Possible values are:

• progressing - The download is in-progress.
• completed - The download completed successfully.
• cancelled - The download has been cancelled.
• interrupted - The download has interrupted.