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Response.bodyUsed

The bodyUsed read-only property of the Response interface is a boolean value that indicates whether the body has been read yet.

Value

A boolean value.

Examples

In our fetch request example (run fetch request live), we create a new request using the Request() constructor, then use it to fetch a JPG. When the fetch is successful, we read a Blob out of the response using blob(), put it into an object URL using URL.createObjectURL, and then set that URL as the source of an <img> element to display the image.

Notice that we log response.bodyUsed to the console once before the response.blob() call and once after. This returns false before and true afterwards, as at that point the body has been read.

HTML Content

<img class="my-image" src="https://wikipedia.org/static/images/project-logos/frwiki-1.5x.png">

JS Content

var myImage = document.querySelector('.my-image');
fetch('https://upload.wikimedia.org/wikipedia/commons/7/77/Delete_key1.jpg').then(function(response) {
    console.log(response.bodyUsed);
    var res = response.blob();
    console.log(response.bodyUsed);
    return res;
}).then(function(response) {
    var objectURL = URL.createObjectURL(response);
    myImage.src = objectURL;
});

Specifications

Specification
Fetch Standard # ref-for-dom-body-bodyused①

Browser compatibility

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	WebView Android	Chrome Android	Firefox for Android	Opera Android	Safari on IOS	Samsung Internet
`bodyUsed`	42	14	39	No	29	10.1	42	42	39	29	10.3	4.0