electron/docs/api/download-item.md
Haojian Wu 1879392c7b Reimplement downloadItem.getFilename API.
Previously, the suggested file name(Always 'empty') returned by
'download_item->GetSuggestedFilename' is not the same with the default one saved
in local disk.

The patch reimplement this API allowing it to return the default file name, which
is more expected from user.
2015-09-24 16:39:02 +08:00

101 lines
2.8 KiB
Markdown

# DownloadItem
`DownloadItem` is an EventEmitter represents a download item in Electron. It
is used in `will-download` event of `Session` module, and allows users to
control the download item.
```javascript
// In the main process.
win.webContents.session.on('will-download', function(event, item, webContents) {
// Set the save path, making Electron not to prompt a save dialog.
item.setSavePath('/tmp/save.pdf');
console.log(item.getMimeType());
console.log(item.getFilename());
console.log(item.getTotalBytes());
item.on('updated', function() {
console.log('Received bytes: ' + item.getReceivedBytes());
});
item.on('done', function(e, state) {
if (state == "completed") {
console.log("Download successfully");
} else {
console.log("Download is cancelled or interrupted that can't be resumed");
}
});
```
## Events
### Event: 'updated'
Emits when the `downloadItem` gets updated.
### Event: 'done'
* `event` Event
* `state` String
* `completed` - The download completed successfully.
* `cancelled` - The download has been cancelled.
* `interrupted` - An error broke the connection with the file server.
Emits when the download is in a terminal state. This includes a completed
download, a cancelled download(via `downloadItem.cancel()`), and interrputed
download that can't be resumed.
## 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.resume()`
Resumes the download that has been paused.
### `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.