4 KiB
DownloadItem
Control file downloads from remote sources.
Process: Main
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.
const {BrowserWindow} = require('electron')
let win = new BrowserWindow()
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
Eventstate
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
Eventstate
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.getSavePath()
Returns String
- The save path of the download item. This will be either the path
set via downloadItem.setSavePath(path)
or the path selected from the shown
save dialog.
downloadItem.pause()
Pauses the download.
downloadItem.isPaused()
Returns Boolean
- Whether the download is paused.
downloadItem.resume()
Resumes the download that has been paused.
downloadItem.canResume()
Resumes Boolean
- Whether the download can resume.
downloadItem.cancel()
Cancels the download operation.
downloadItem.getURL()
Returns String
- The origin url where the item is downloaded from.
downloadItem.getMimeType()
Returns String
- The files mime type.
downloadItem.hasUserGesture()
Returns Boolean
- Whether the download has user gesture.
downloadItem.getFilename()
Returns String
- 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 Integer
- The total size in bytes of the download item.
If the size is unknown, it returns 0.
downloadItem.getReceivedBytes()
Returns Integer
- The received bytes of the download item.
downloadItem.getContentDisposition()
Returns String
- The Content-Disposition field from the response
header.
downloadItem.getState()
Returns String
- The current state.
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.