Question

177

XMLHttpRequest is always calling load event listener, even when response has error status

rated 0 times [ 178] [ 1] / answers: 1 / hits: 33523 / 13 Years ago, thu, july 21, 2011, 12:00:00

I'm using FormData to ajax a file upload. The upload works, but the problem is that the error callback is never invoked. Even when my HTTP response is a 500 internal server error (to test this I tweak server to respond with 500), the load callback is invoked.

function upload_image() {

    var form = document.getElementById('upload_image_form');

    var formData = new FormData(form);



    var xhr = new XMLHttpRequest();

    xhr.addEventListener(load, function(e) {

        alert(Success callback);

    }, false);

    xhr.addEventListener(error, function(e) {

        alert(Error callback);

    }, false);

    xhr.open(POST, /upload_image);

    xhr.send(formData);

}

Any ideas? I'm testing this on Chrome.

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xiomara

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3 Years ago

answered 13 Years ago raymondorlandok · Accepted Answer

This setup should work better for your needs:

var req = new XMLHttpRequest();

req.open('POST', '/upload_image');

req.onreadystatechange = function (aEvt) {

  if (req.readyState == 4) {

     if(req.status == 200)

      alert(req.responseText);

     else

      alert(Error loading pagen);

  }

};

req.send(formData);

In your code error callback is never called because it is only triggered by network-level errors, it ignores HTTP return codes.