loadImageViaBlob
Asynchronously loads the given image URL by first downloading it as a blob using XMLHttpRequest and then loading the image from the buffer via a blob URL. This allows access to more information that is not accessible via normal Image-based downloading, such as the size of the response. This function returns a promise that will resolve to an Image once loaded, or reject if the image failed to load. The returned image will have a "blob" property with the Blob itself. If the browser does not support an XMLHttpRequests with a responseType of 'blob', or if the provided URI is a data URI, this function is equivalent to calling loadImage, and the extra blob property will not be present.
Parameters:
| Name | Type | Description |
|---|---|---|
url |
String | Promise | The source of the image, or a promise for the URL. |
Returns:
Promise
a promise that will resolve to the requested data when loaded.
Example
// load a single image asynchronously
loadImageViaBlob('some/image/url.png').then(function(image) {
var blob = image.blob;
// use the loaded image or XHR
}, function() {
// an error occurred
});
// load several images in parallel
when.all([loadImageViaBlob('image1.png'), loadImageViaBlob('image2.png')]).then(function(images) {
// images is an array containing all the loaded images
});