JSFiddle - React, Tailwind, and code Playground

HTML

<input type="text" size="30" id="imageInput" placeholder="Enter URL">
  <input type="text" size="30" id="captionInput" placeholder="Enter Caption">
  <input type="button" value="Add Image" onclick="addImage();"/>

JavaScript

(function(window) {
    window['annotatedImageArray'] = [];
    window['addImage'] = function() {
        var imageInput = document.getElementById("imageInput");
        var image = imageInput.value;
        var captionInput = document.getElementById("captionInput");
        var caption1 = captionInput.value;
        annotatedImageArray.push({url:image, caption:caption1});
    }
})(window);