# DownloadTask wx.downloadFile(Object object)

with Promise style call: Not supported

Mini Program plugin: Support, need to Mini Program base library version no less than 1.9.6

Download file resources to the local. The client directly initiates a HTTPS GET Request, return the local temporary path to the file (Local path)The maximum file allowed for a single download is 200MB。 Please read carefully before usingRelated notes。

Note: Please click the header Specifies a reasonable Content-Type Field to ensure that the client handles file types correctly.

# parameter

# Object object

attribute	type	Required	Introductions	Minimum version
url	string	yes	Download resource url
header	Object	no	HTTP Requested Header，Header Can not be set Refer
timeout	number	no	Timeout in milliseconds	2.10.0
filePath	string	no	Specify the path to store files after they are downloaded (Local path)	1.8.0
success	function	no	Interface calls the successful callback function
fail	function	no	Interface calls failed callback functions
complete	function	no	Callback function at the end of an interface call (both successful and unsuccessful calls are executed)

# object.success callback

# parameter

# Object res

attribute	type	Introductions	Minimum version
tempFilePath	string	Temporary file path (Local path)No incoming filePath When you specify a file storage path, the downloaded file is stored in a temporary file
filePath	string	User File Path (Local path)Incoming. filePath Is returned when the filePath Agreement
statusCode	number	Returned by the developer server HTTP Status code
profile	Object	Some debugging information during the network request,View details	2.10.4

res.profile Structure

attribute	type	Introductions
redirectStart	number	The first. HTTP The time when the redirection occurred. There is a jump and redirection within the same domain, otherwise the value is 0
redirectEnd	number	Last one. HTTP Time at which the redirection completes. Redirects within the same domain with a jump, otherwise the value is 0
fetchStart	number	Components ready to use HTTP Request time to fetch resource, before checking local cache
初始值	number	初始值初始值初始值初始值 fetchStart 初始值
domainLookupEnd	number	DNS When the domain name query was completed, if local caching was used DNS Query) or persistent connection, with the fetchStart Value equality
connectStart	number	HTTP（TCP） When a connection is established, and if the connection is persistent, the fetchStart Values are equal. Note that if an error occurs at the transport layer and a connection is reestablished, this shows the time when the newly established connection started
connectEnd	number	HTTP（TCP） Time to complete the connection establishment (complete handshake), or if the connection is persistent, with the fetchStart Values are equal. Note that if an error occurs at the transport layer and the connection is reestablished, the time when the newly established connection was completed is shown here. Note the end of the handshake, including the establishment of the security connection, SOCKS Authorized by
SSLconnectionStart	number	Time when the SSL connection was established, or if it is not a secure connection, the value is 0
SSLconnectionEnd	number	Time when SSL is established, or if it is not a secure connection, the value is 0
requestStart	number	The time when the HTTP request started reading the real document (complete connection establishment), including reading the cache locally. When the connection is reconnected, the time of the new connection is also shown here
requestEnd	number	When the HTTP request reads the real document ends
responseStart	number	HTTP Time to start receiving the response (first byte), including reading the cache locally
responseEnd	number	HTTP Time when the response is complete (to the last byte), including reading the cache locally
rtt	number	When a request is connected in real time rtt
estimate_nettype	number	Network State Assessment unknown, offline, slow 初始值初始值 3g, 4g, 初始值/初始值 1, 2, 3, 4, 5, 6
httpRttEstimate	number	The protocol layer evaluates the current network's Rtt (for reference only)
transportRttEstimate	number	Of the current network evaluated by the transport layer based on multiple requests Rtt (for reference only)
downstreamThroughputKbpsEstimate	number	Evaluate kbps for current network downloads
throughputKbps	number	Actual downloads from the current network kbps
peerIP	string	IP currently requested
port	number	Port currently requested
socketReused	boolean	Reusing connections
sendBytesCount	number	Number of bytes sent
receivedBytedCount	number	Number of bytes received
protocol	string	Using protocol type, valid value: http 1.1, h2, quic, unknown

# Return value

# DownloadTask

Start from base library version 1.4.0. Please remaining backward compatible.

An object that can listen for download progress changes and cancel downloads

# sample code

wx.downloadFile({
  url: 'https://example.with/audio/123', //Just an example, not a real resource.
  success (res) {
    // As long as the server has the response data, the response will be written to a file and entered success Callback, the business needs to determine whether to download the desired content
    if (res.statusCode === 200) {
      wx.playVoice({
        filePath: res.tempFilePath
      })
    }
  }
})