Peter Lubbers - Pro HTML 5 Programming

crossOriginRequest.upload.onprogress = function(e) {
var total = e.total;
var loaded = e.loaded;
}
if (e.lengthComputable) {
// do something with the progress information
}
Building an Application Using XMLHttpRequest
CHAPTER 5 ■ USING THE COMMUNICATION APIS
In this example, we’ll look at uploading race geolocation coordinates to a web server hosted on a
different origin. We use the new progress events to monitor the status of the HTTP request including the
upload percentage. Figure 5-5 shows the application in action.
Figure 5-5. A web application that uploads geolocation data
For the sake of illustration, we’ve created the HTML file crossOrignUpload.html. The following steps
highlight the important parts of building the cross-origin upload page shown in Figure 5-5. The sample
code for the following examples is located in the code/communication folder.
First, create a new XMLHttpRequest object, as shown in the following example.
var xhr = new XMLHttpRequest();
Next, do check if cross-origin XMLHttpRequest is supported in the browser, as shown in the
following example.
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