How to use js to check if the computer is connected to the network?

Question

JavaScript

<img id="bannerImg" class="image" crossOrigin="*" src="https://upload.wikimedia.org/wikipedia/commons/thumb/8/8b/Proton-K-Zarya.jpg/800px-Proton-K-Zarya.jpg" />
<img id="tableBanner" class="image" crossOrigin="*" src="https://upload.wikimedia.org/wikipedia/commons/e/e8/Richard_of_Shrewsbury%2C_1._Duke_of_York.jpg?download" />

var images = document.querySelectorAll('.image');
if (images.length > 0) {
  // в Storage
  var dataArray = [];
  for (var i = 0, itemsLength = images.length; i < itemsLength; i++) {
    dataArray.push({
      img: getBase64Image(images[i]),
      id: images[i].id || ''
    });
  }
  localStorage.setItem("imagesData", JSON.stringify(dataArray));

  //из Storage
  var storageArray = JSON.parse(localStorage.getItem('imagesData'));
  if (Array.isArray(storageArray)) {
    storageArray.map(function(dataImage) {
      var element = document.getElementById(dataImage.id);
      if (element) {
        element.src = "data:image/png;base64," + dataImage.img;
      }
    });
  }
}

function getBase64Image(img) {
  var canvas = document.createElement("canvas");
  canvas.width = img.width;
  canvas.height = img.height;

  var ctx = canvas.getContext("2d");
  ctx.drawImage(img, 0, 0);

  var dataURL = canvas.toDataURL("image/png");

  return dataURL.replace(/^data:image\/(png|jpg);base64,/, "");
}

Here is the fiddle code: jsfiddle.net/zolotnitskiy/4ra8nhk4/4

Answer 1

stackoverflow.com/questions/2384167/check-if-inter...