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How to instantiate a File object in JavaScript?

There's a File object in JavaScript. I want to instantiate one for testing purposes.

I have tried new File(), but I get an "Illegal constructor" error.

Is it possible to create a File object ?

File Object reference : https://developer.mozilla.org/en/DOM/File

Solution

  • According to the W3C File API specification, the File constructor requires 2 (or 3) parameters.

    So to create a empty file do:

    var f = new File([""], "filename");
    • The first argument is the data provided as an array of lines of text;
    • The second argument is the filename ;

    • The third argument looks like:

      var f = new File([""], "filename.txt", {type: "text/plain", lastModified: date})

    It works in FireFox, Chrome and Opera, but not in Safari or IE/Edge.