Why Javascript upload chunk sizes change by browser?

Question

I am uploading files by javascript code to server. I noticed that different browsers are sending bytes of different sizes. As you can see in the following pictures, Internet

Answer 1

I don't know why it's different, but you can alter your behavior based on the browser (as opposed to standardizing as you asked in the question).

Refer to the code in the moo uploader as an example.

From: https://github.com/juanparati/MooUpload/blob/master/Source/MooUpload.js

    // Get slice method
    if (file.mozSlice)          // Mozilla based
      chunk = file.mozSlice(start, total)
    else if (file.webkitSlice)  // Chrome, Safari, Konqueror and webkit based
      chunk = file.webkitSlice(start, total);
    else                        // Opera and other standards browsers
      chunk = file.slice(start, total)