FileList behaves incorrectly in a couple different ways

Issue #7475645 • Assigned to Shawn P.


Michael W.
May 6, 2016
This issue is public.
Found in
  • Microsoft Edge
Standard affected
File API

Found in build #
Reported by 1 person

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Steps to reproduce

Discovered when iterating through the properties of a FileList as though it were an array.

I’ve attached a rudimentary test file to demonstrate these behaviors, but I’ll describe them here:

First, FileList.prototype.hasOwnProperty always returns, making iteration difficult:

for (const index in myFileList) {
  if (myFileList.hasOwnProperty(index)) {
    // Nothing in here executes because FileList.prototype.hasOwnProperty
    // always returns false

Second, FileList.prototype.item is supposed to return the File item at a given index. It will also return a file if given a string:

myFileList.item(0) // => [object File]
myFileList.item(1) // => no item, this imaginary input has just one file
myFileList.item("any string") // => [object File]


1 attachment

Comments and activity

  • Microsoft Edge Team

    Changed Assigned To to “Ibrahim O.”

    Changed Assigned To to “Travis L.”

    Changed Assigned To to “Venkat K.”

    Changed Assigned To from “Venkat K.” to “Shawn P.”

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