GlobalEventHandlers.onloadstart

The onloadstart property of the GlobalEventHandlers mixin is an EventHandler representing the code to be called when the loadstart event is raised (when progress has begun on the loading of a resource.)

img.onloadstart = funcRef;

funcRef is the handler function to be called when the resource's loadstart event fires.

<img src="myImage.jpg">

// 'loadstart' fires first, then 'load', then 'loadend'

image.addEventListener('load', function(e) {
  console.log('Image loaded');
});

image.addEventListener('loadstart', function(e) {
  console.log('Image load started');
});

image.addEventListener('loadend', function(e) {
  console.log('Image load finished');
});