URLSaveAsynchronous is being phased out in favor of URLDownloadSubmit, which was introduced experimentally in Version 11.2.


performs a download to "file" in the background, calling func when an event is raised.

Details and Options

  • Types of events that may be raised:
  • "data"returns an empty list; can be used to indicate the connection has completed
    "progress"returns information about the current connection of the form {dlnow,dltotal,ulnow,ultotal}
    "error"indicates that an error occurred while attempting to connect to the URL
    "headers"headers received from the web server
    "cookies"a list of all known cookies
    "statuscode"the status code returned by the server
  • The following options can be given:
  • Method"GET"method to use for request
    "Parameters"{}parameters to be sent for the request
    "Body"""contents of message body to be sent
    "MultipartElements"{}list of multipart data elements to send
    "Username"""username to use for the request
    "Password"""password to use for the request
    "Headers"{}headers to be manually sent to the HTTP server
    "Cookies"Truecookies to pass to the server
    "StoreCookies"Automaticwhether to store received cookies
    "VerifyPeer"Trueverify authenticity using SSL certificates
    "UserAgent"Automaticuser agent string to send
    "ReadTimeout"0time to allow for uploading or downloading data
    "ConnectTimeout"0time to allow for connecting to the server
    "Progress"Falsewhether to raise a "progress" event
    "Transfer"Automaticif Automatic, the "data" event returns once and returns all the data downloaded; if "Chunks", the "data" event is raised multiple times with the data downloaded since the last event was raised
    "UserData"Noneany expression passed to this option will be stored for use of the AsynchronousTaskObject inside the event function; the data can be found by checking the options of AsynchronousTaskObject passed to the event function
    BinaryFormatTruewhether to avoid textual interpretation of newlines or other data
    "FollowRedirects"Truewhether to follow redirects
  • When an event is raised, the event function passed to URLSaveAsynchronous will be executed. The event functions will be passed three arguments, the AsynchronousTaskObject, the event name, and the data received from the event. Event functions are the only method for handling data received from URLSaveAsynchronous.


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Basic Examples  (1)

Monitor progress while downloading the contents of a URL to a file:

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Options  (15)

Properties & Relations  (1)

Introduced in 2012