Achieve Invisible Upload in JavaScript (ES5) Uploader control

18 May 2022 / 1 minute to read

You can achieve the invisible upload feature by using the selected event in uploader component. Refer to the following example.

Source

Preview

index.js

index.html

index.css

// initialize Uploader component
var uploadObject = new ej.inputs.Uploader({
    asyncSettings: {
        saveUrl: 'https://ej2.syncfusion.com/services/api/uploadbox/Save',
        removeUrl: 'https://ej2.syncfusion.com/services/api/uploadbox/Remove'
    },
    selected : onupload,
    locale: 'en-US',
    allowedExtensions: '.png, .jpg, .jpeg'
});

// render initialized Uploader
uploadObject.appendTo('#fileupload');

function onupload(args) {    
    for(var i = 0; i< args.filesData.length ; i++){
        var liparentDiv = createElement('div',  { className: 'image-list'});
        var liImage = createElement('img',  { className: 'image'});
        liparentDiv.appendChild(liImage);
        readURL(liImage, args.filesData[i]);
        document.getElementById('preview').appendChild(liparentDiv);
    }
    args.cancel=true;
}

function readURL(liImage, file) {
    var imgPreview = liImage;
    var imageFile = file.rawFile;
    var reader = new FileReader();
    reader.addEventListener( 'load', () => {
        imgPreview.src = reader.result;
    }, false);
    if (imageFile) {
        reader.readAsDataURL(imageFile);
    }
};

<!DOCTYPE html><html lang="en"><head>
    <title>Essential JS 2 Uploader</title>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta name="description" content="Essential JS 2 Uploader Component">
    <meta name="author" content="Syncfusion">
    <link href="index.css" rel="stylesheet">
    <link href="//cdn.syncfusion.com/ej2/20.1.55/ej2-base/styles/material.css" rel="stylesheet">
    <link href="//cdn.syncfusion.com/ej2/20.1.55/ej2-inputs/styles/material.css" rel="stylesheet">
    <link href="//cdn.syncfusion.com/ej2/20.1.55/ej2-popups/styles/material.css" rel="stylesheet">
    <link href="//cdn.syncfusion.com/ej2/20.1.55/ej2-buttons/styles/material.css" rel="stylesheet">
    
    
<script src="https://cdn.syncfusion.com/ej2/20.1.55/dist/ej2.min.js" type="text/javascript"></script>
</head>
<body>
    
    <div id="preview"></div>
    <div id="container">
        <input type="file" id="fileupload" name="UploadFiles">
    </div>

<script>
var ele = document.getElementById('container');
if(ele) {
    ele.style.visibility = "visible";
 }   
        </script>
<script src="index.js" type="text/javascript"></script>
</body></html>

#container {
  visibility: hidden;
  margin: 10px;
}

#loader {
  color: #008cff;
  font-family: 'Helvetica Neue','calibiri';
  font-size: 14px;
  height: 40px;
  left: 45%;
  position: absolute;
  top: 45%;
  width: 30%;
}

#preview {
  border: 2px dashed #ddd;
  padding: 15px;
}

.image-list {
  width: 134px;
  height: 117px;
  margin-right: 4px;
  border: 1px solid lightgrey;
  display: inline-block;
}

.image {
  width: 134px;
  height: 117px;
  margin-right: 4px;
  display: inline-block;
}

.e-control {
  border : 0;
}

.e-control ul {
  border: 1px solid #ddd;
}

.e-control .e-file-select,
.e-control .e-file-drop {
  display: none;
}

You can also explore JavaScript File Upload feature tour page for its groundbreaking features. You can also explore our JavaScript File Upload example to understand how to browse the files which you want to upload to the server.