bn.downloadFile

▸ downloadFile(options): DownloadTask

description Download file from url

example

bn.downloadFile({ url: 'https://example.com/audio/123', //example, not real path success (res) {   // If only server responses, response data will be write into file and call success callback.   // need to check whether the content is correct if you need.   if (res.statusCode === 200) {    wx.playVoice({      filePath: res.tempFilePath    })  }}})

Parameters

Name	Type	Description
options	DownloadFileOption	download file options

Returns

DownloadTask

DownloadTask - A task object that can be used to control and query the download

Interface: DownloadFileOption

Name	Type	Description
url	string	requested resource's url
header?	Record<string, string>	HTTP request header, cannot set referer here
timeout?	number	timeoutdefault 2000
filePath?	string	save path after file is downloaded
success?	(result): void	success callback
fail?	(res): void	fail callback
complete?	(res): void	complete callback

success

▸ Optional success(result): void

success callback

Parameters

Name	Type
result	DownloadSuccessCallbackResult

Returns

void

---

fail

▸ Optional fail(res): void

fail callback

Parameters

Name	Type
res	GeneralCallbackResult

Returns

void

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complete

▸ Optional complete(res): void

complete callback

Parameters

Name	Type
res	GeneralCallbackResult

Returns

void

Interface: DownloadSuccessCallbackResult

Name	Type	Description
filePath?	string	File path. Same as filePath in parameter
statusCode	number	Server HTTP status code
tempFilePath?	string	Temp file path, if no filePath in parameter, file will be saved in a temp file path
errMsg	string	Call result

Interface: GeneralCallbackResult

Name	Type	Description
errMsg	string

Interface: DownloadTask

Name	Type	Description
abort	(): void	abort download task
offHeadersReceived	(callback?): void	un-listen HTTP Response Header event
offProgressUpdate	(callback?): void	un-listen download task progress update event
onHeadersReceived	(callback): void	listen HTTP Response Header event. Triggered before task completes
onProgressUpdate	(callback): void	listen download task progress update event

abort

▸ abort(): void

abort download task

Returns

void

---

offHeadersReceived

▸ offHeadersReceived(callback?): void

un-listen HTTP Response Header event

Parameters

Name	Type
callback?	OffHeadersReceivedCallback

Returns

void

---

offProgressUpdate

▸ offProgressUpdate(callback?): void

un-listen download task progress update event

Parameters

Name	Type
callback?	DownloadTaskOffProgressUpdateCallback

Returns

void

---

onHeadersReceived

▸ onHeadersReceived(callback): void

listen HTTP Response Header event. Triggered before task completes

Parameters

Name	Type
callback	OnHeadersReceivedCallback

Returns

void

---

onProgressUpdate

▸ onProgressUpdate(callback): void

listen download task progress update event

Parameters

Name	Type
callback	DownloadTaskOnProgressUpdateCallback

Returns

void

OffHeadersReceivedCallback

Ƭ OffHeadersReceivedCallback: (result: OnHeadersReceivedCallbackResult) => void

Type declaration

▸ (result): void

Parameters

Name	Type
result	OnHeadersReceivedCallbackResult

Returns

void

---

Interface: OnHeadersReceivedCallbackResult

Name	Type	Description
header	Headers	开发者服务器返回的 HTTP Response Header

DownloadTaskOffProgressUpdateCallback

Ƭ DownloadTaskOffProgressUpdateCallback: (result: DownloadTaskOnProgressUpdateCallbackResult) => void

Type declaration

▸ (result): void

Parameters

Name	Type
result	DownloadTaskOnProgressUpdateCallbackResult

Returns

void

---

Interface: DownloadTaskOnProgressUpdateCallbackResult

Name	Type	Description
progress	number	下载进度百分比
totalBytesExpectedToWrite	number	预期需要下载的数据总长度，单位 Bytes
totalBytesWritten	number	已经上传的数据长度，单位 Bytes

OnHeadersReceivedCallback

Ƭ OnHeadersReceivedCallback: (result: OnHeadersReceivedCallbackResult) => void

Type declaration

▸ (result): void

Parameters

Name	Type
result	OnHeadersReceivedCallbackResult

Returns

void

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DownloadTaskOnProgressUpdateCallback

Ƭ DownloadTaskOnProgressUpdateCallback: (result: DownloadTaskOnProgressUpdateCallbackResult) => void

Type declaration

▸ (result): void

Parameters

Name	Type
result	DownloadTaskOnProgressUpdateCallbackResult

Returns

void

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