easia/public/assets/js/form-wizard/image-upload.js

(function () {
    document
      .getElementById("imageUpload")
      .addEventListener("change", readURL, true);
    function readURL() {
      const file = document.getElementById("imageUpload").files[0];
      const reader = new FileReader();
      reader.onloadend = function () {
        document.getElementById("image").style.backgroundImage =
          "url(" + reader.result + ")";
      };
      if (file) {
        reader.readAsDataURL(file);
      } else {
      }
    }
  })();