Deprecated: This feature is no longer recommended. Though some browsers might still support it, it may have already been removed from the relevant web standards, may be in the process of being dropped, or may only be kept for compatibility purposes. Avoid using it, and update existing code if possible; see the compatibility table at the bottom of this page to guide your decision. Be aware that this feature may cease to work at any time.
Non-standard: This feature is non-standard and is not on a standards track. Do not use it on production sites facing the Web: it will not work for every user. There may also be large incompatibilities between implementations and the behavior may change in the future.
FileSystemEntry interface's method
toURL() creates and
returns a string containing a URL which can be used to identify the file system entry.
This is done by exposing a new URL scheme—
filesystem:—that can be used as
the value of
An optional string specifying the MIME type to use when interpreting the file. This can be used to help deal with files whose types aren't recognized automatically by the user agent. If this parameter is omitted, the user agent uses its standard algorithms to identify the file.
A string containing a URL that can then be used as a document
reference in HTML content, or an empty string if the URL can't be generated (such as if
the file system implementation doesn't support
If you have a
FileSystemFileEntry corresponding to an image file in a
file system available to your website or app, you can call
toURL() to get
its URL for use in HTML. If your site is located at
http://my-awesome-website.woot, and you have a temporary file system that
contains an image file named
awesomesauce.jpg, the URL returned by
toURL() might be (depending on the browser's implementation) something like
Code that makes use of this might look like this:
let img = document.createElement("img");
img.src = imageFileEntry.toURL();
Assuming the scenario mentioned before the code, the result would be HTML that looks like this being appended to the end of the document:
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