Get API or File Size

This code sample will allow you to retrieve the size of a file or API response without actually downloading it (server needs to provide Content-Length header).

function getApiSize(url) {
    var req = new XMLHttpRequest();
    req.open("HEAD", url, false);
    req.send(null);
    console.log(req.getResponseHeader('Content-Length'));
}

Directions:
- Call getApiSize(url); and you will see the size in your console.

Note:
This snippet focuses on iOS development. Make sure to verify/adapt any vendor prefixes. Back to main listing.

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