Preview an image before it is uploaded

I want to be able to preview a file (image) before it is uploaded. The preview action should be executed all in the browser without using Ajax to upload the image.

How can I do this?

imgInp.onchange = evt => {
const [file] = imgInp.files
if (file) {
blah.src = URL.createObjectURL(file)
}
}





Stack Overflow Q#4459379, score: 3375