问题
Does the Chrome Javascript API support downloading a file in several chunks simultaneously? eg in a download manager.
回答1:
Short answer: no, no special support. There is a dedicated chrome.downloads API, but it's just the same mechanism as normal Chrome downloads, i.e. single stream.
Long answer: You can make it yourself via XMLHttpRequest by setting range attributes, e.g.
xhr.setRequestHeader("Range", "bytes=100-200");
See more information here, and potential problems you can run into in this question.
来源：https://stackoverflow.com/questions/23309841/download-file-in-chunks-in-chrome-javascript-api