Follow

Keep Up to Date with the Most Important News

By pressing the Subscribe button, you confirm that you have read and are agreeing to our Privacy Policy and Terms of Use
Contact

Only append document if image is valid using jquery

I have an array of image urls that I need to add to a document (shown below). Some of the urls do not contain images. How do I check this?

picUrls = ["https://s3-us-west-1.amazonaws.com/codesmith-precourse-images/048.jpg","https://s3-us-west-1.amazonaws.com/codesmith-precourse-images/18166-shivling-whatsapp-image-and-dp.jpg","http://www.fakeurl.io/fakeimage1.jpeg","https://s3-us-west-1.amazonaws.com/codesmith-precourse-images/18416-navratri-image-for-whatsapp-and-facebook.jpg"]

I am using jquery and have tried the .load & .error

for(let i = 0; i < picUrls.length; i++) {
    const picUrl = picUrls[i];

    //create image to preload:
    var imgPreload = new Image();
    $(imgPreload).attr({
      src: picUrl
    });
    
    //check if the image is already loaded (cached):
    if (imgPreload.complete || imgPreload.readyState === 4) {
    
      //image loaded:
      //your code here to insert image into page
      $('#content-container').append(imgPreload);
    
    } else {
      //go fetch the image:
      $(imgPreload).load(function (response, status, xhr) {
        if (status == 'error') {
    
          //image could not be loaded:
          console.log('error');
        } else {
    
          //image loaded:
          //your code here to insert image into page
          $('#content-container').append(imgPreload);
    
        }
      });

MEDevel.com: Open-source for Healthcare and Education

Collecting and validating open-source software for healthcare, education, enterprise, development, medical imaging, medical records, and digital pathology.

Visit Medevel

>Solution :

You can create a helper function that returns a promise whether an image is a valid image or not

      const picUrls = [
        'https://s3-us-west-1.amazonaws.com/codesmith-precourse-images/048.jpg',
        'https://s3-us-west-1.amazonaws.com/codesmith-precourse-images/18166-shivling-whatsapp-image-and-dp.jpg',
        'http://www.fakeurl.io/fakeimage1.jpeg',
        'https://s3-us-west-1.amazonaws.com/codesmith-precourse-images/18416-navratri-image-for-whatsapp-and-facebook.jpg',
      ];

      const getOnlyValidImage = src =>
        new Promise((resolve, reject) => {
          const img = new Image();
          img.src = src;
          img.onload = () => resolve(img);
          img.onerror = () => resolve(null);
        });

      const preloadImages = async () => {
        for (let i = 0; i < picUrls.length; i++) {
          const picUrl = picUrls[i];
          const image = await getOnlyValidImage(picUrl)
          if (image) {
            $('#content-container').append(image);
          }
        }
      };

      preloadImages();
Add a comment

Leave a Reply

Keep Up to Date with the Most Important News

By pressing the Subscribe button, you confirm that you have read and are agreeing to our Privacy Policy and Terms of Use

Discover more from Dev solutions

Subscribe now to keep reading and get access to the full archive.

Continue reading