JSFiddle - React, Tailwind, and code Playground

HTML

<input type=file id=imgChooser>
<img id=preview>

JavaScript

function readImage() {
    if (this.files && this.files[0]) {
        var file = new FileReader();
        file.onload = function(e) {
            document.getElementById("preview").src = e.target.result;
        };       
        file.readAsDataURL(this.files[0]);
    }
}

document.getElementById("imgChooser").addEventListener("change", readImage, false);