In my HTML form I have input filed with type file for example :
<input type="file" multiple>
Then I'm selecting multiple files by clicking that input button.
Now I want to show preview of selected images before submitting form . How to do that in HTML 5?
Here's a quick example that makes use of the URL.createObjectURL to render a thumbnail by setting the src attribute of an image tag to a object URL:
The html code:
<input accept="image/*" type="file" id="files" />
<img id="image" />
The JavaScript code:
document.getElementById('files').onchange = function () {
var src = URL.createObjectURL(this.files[0])
document.getElementById('image').src = src
}
The code snippet in the HTML example below filters out images from the user's selection and renders selected files into multiple thumbnail previews:
function handleFileSelect (evt) {
// Loop through the FileList and render image files as thumbnails.
for (const file of evt.target.files) {
// Render thumbnail.
const span = document.createElement('span')
const src = URL.createObjectURL(file)
span.innerHTML =
`<img style="height: 75px; border: 1px solid #000; margin: 5px"` +
`src="${src}" title="${escape(file.name)}">`
document.getElementById('list').insertBefore(span, null)
}
}
document.getElementById('files').addEventListener('change', handleFileSelect, false);
<input type="file" accept="image/*" id="files" multiple />
<output id="list"></output>
Here I did with jQuery using FileReader API.
Html Markup:
<input id="fileUpload" type="file" multiple />
<div id="image-holder"></div>
jQuery:
Here in jQuery code,first I check for file extension. i.e valid image file to be processed, then will check whether the browser support FileReader API is yes then only processed else display respected message
$("#fileUpload").on('change', function () {
//Get count of selected files
var countFiles = $(this)[0].files.length;
var imgPath = $(this)[0].value;
var extn = imgPath.substring(imgPath.lastIndexOf('.') + 1).toLowerCase();
var image_holder = $("#image-holder");
image_holder.empty();
if (extn == "gif" || extn == "png" || extn == "jpg" || extn == "jpeg") {
if (typeof (FileReader) != "undefined") {
//loop for each file selected for uploaded.
for (var i = 0; i < countFiles; i++) {
var reader = new FileReader();
reader.onload = function (e) {
$("<img />", {
"src": e.target.result,
"class": "thumb-image"
}).appendTo(image_holder);
}
image_holder.show();
reader.readAsDataURL($(this)[0].files[i]);
}
} else {
alert("This browser does not support FileReader.");
}
} else {
alert("Pls select only images");
}
});
function handleFileSelect(evt) {
var files = evt.target.files;
// Loop through the FileList and render image files as thumbnails.
for (var i = 0, f; f = files[i]; i++) {
// Only process image files.
if (!f.type.match('image.*')) {
continue;
}
var reader = new FileReader();
// Closure to capture the file information.
reader.onload = (function(theFile) {
return function(e) {
// Render thumbnail.
var span = document.createElement('span');
span.innerHTML =
[
'<img style="height: 75px; border: 1px solid #000; margin: 5px" src="',
e.target.result,
'" title="', escape(theFile.name),
'"/>'
].join('');
document.getElementById('list').insertBefore(span, null);
};
})(f);
// Read in the image file as a data URL.
reader.readAsDataURL(f);
}
}
document.getElementById('files').addEventListener('change', handleFileSelect, false);
<input type="file" id="files" multiple />
<output id="list"></output>
For background images, make sure to use url()
node.backgroundImage = 'url(' + e.target.result + ')';
Without FileReader, we can use URL.createObjectURL method to get the DOMString that represents the object ( our image file ).
Don't forget to validate image extension.
<input type="file" id="files" multiple />
<div class="image-preview"></div>
let file_input = document.querySelector('#files');
let image_preview = document.querySelector('.image-preview');
const handle_file_preview = (e) => {
let files = e.target.files;
let length = files.length;
for(let i = 0; i < length; i++) {
let image = document.createElement('img');
// use the DOMstring for source
image.src = window.URL.createObjectURL(files[i]);
image_preview.appendChild(image);
}
}
file_input.addEventListener('change', handle_file_preview);
Related
Consider this javascript code, I wanna be able to manipulate the size of the image after it gets uploaded to the browser. I'm new to javascript any help I would be grateful!
file.js:
const fileSelect = document.getElementById("fileSelect"),
fileElem = document.getElementById("fileElem"),
fileList = document.getElementById("fileList");
fileSelect.addEventListener("click", function (e) {
if (fileElem) {
fileElem.click();
}
e.preventDefault(); // prevent navigation to "#"
}, false);
fileElem.addEventListener("change", handleFiles, false);
function handleFiles() {
if (!this.files.length) {
fileList.innerHTML = "<p>No files selected!</p>";
} else {
fileList.innerHTML = "";
const list = document.createElement("ul");
fileList.appendChild(list);
for (let i = 0; i < this.files.length; i++) {
const li = document.createElement("li");
list.appendChild(li);
const img = document.createElement("img");
img.src = URL.createObjectURL(this.files[i]);
img.height = 60;
img.onload = function () {
URL.revokeObjectURL(this.src);
}
li.appendChild(img);
}
}
}
html file:
<body>
<input type="file" id="fileElem" multiple accept="image/*" style="display:none">
Select some files
<div id="fileList">
<p>No files selected!</p>
</div>
<!-- ************** js ********** -->
<script src="./file.js" type="text/javascript"></script>
</body>
I want to show contents of uploaded file in html, I can just upload a text file.
My example.html:
<html xmlns="http://www.w3.org/1999/xhtml" >
<p>
Please specify a file, or a set of files:<br>
<input type="file" name="datafile" size="40">
</p>
<textarea id="2" name="y" style="width:400px;height:150px;"></textarea>
</html>
How can I show contents of any uploaded text file in textarea shown below?
I've came here from google and was surprised to see no working example.
You can read files with FileReader API with good cross-browser support.
const reader = new FileReader()
reader.onload = event => console.log(event.target.result) // desired file content
reader.onerror = error => reject(error)
reader.readAsText(file) // you could also read images and other binaries
See fully working example below.
document.getElementById('input-file')
.addEventListener('change', getFile)
function getFile(event) {
const input = event.target
if ('files' in input && input.files.length > 0) {
placeFileContent(
document.getElementById('content-target'),
input.files[0])
}
}
function placeFileContent(target, file) {
readFileContent(file).then(content => {
target.value = content
}).catch(error => console.log(error))
}
function readFileContent(file) {
const reader = new FileReader()
return new Promise((resolve, reject) => {
reader.onload = event => resolve(event.target.result)
reader.onerror = error => reject(error)
reader.readAsText(file)
})
}
label {
cursor: pointer;
}
textarea {
width: 400px;
height: 150px;
}
<div>
<label for="input-file">Specify a file:</label><br>
<input type="file" id="input-file">
</div>
<textarea id="content-target"></textarea>
Here's one way:
HTML
<tr>
<td>Select a File to Load:</td>
<td><input type="file" id="fileToLoad"></td>
<td><button onclick="loadFileAsText()">Load Selected File</button><td>
</tr>
JavaScript
function loadFileAsText(){
var fileToLoad = document.getElementById("fileToLoad").files[0];
var fileReader = new FileReader();
fileReader.onload = function(fileLoadedEvent){
var textFromFileLoaded = fileLoadedEvent.target.result;
document.getElementById("inputTextToSave").value = textFromFileLoaded;
};
fileReader.readAsText(fileToLoad, "UTF-8");
}
Try this.
HTML
<p>
Please specify a file, or a set of files:<br>
<input type="file" id="myFile" multiple size="50" onchange="myFunction()">
</p>
<textarea id="demo" style="width:400px;height:150px;"></textarea>
JS
function myFunction(){
var x = document.getElementById("myFile");
var txt = "";
if ('files' in x) {
if (x.files.length == 0) {
txt = "Select one or more files.";
} else {
for (var i = 0; i < x.files.length; i++) {
txt += (i+1) + ". file";
var file = x.files[i];
if ('name' in file) {
txt += "name: " + file.name + "";
}
if ('size' in file) {
txt += "size: " + file.size + " bytes ";
}
}
}
}
else {
if (x.value == "") {
txt += "Select one or more files.";
} else {
txt += "The files property is not supported by your browser!";
txt += "The path of the selected file: " + x.value; // If the browser does not support the files property, it will return the path of the selected file instead.
}
}
document.getElementById("demo").innerHTML = txt;
}
Demo
I created a very basic example of a multiple file upload form (reference), it works perfect on desktop but not on mobile, at least the ones I am testing with.
On Mobile (Xiaomi Mi4 [Android version: 6.1] - Google Chrome/Mozilla Firefox): When I click on Choose files I see this screen:
If I choose Google Photos and select multiple files, only the first file will be inserted into the form.
If I select the Gallery (native) app and select multiple files I get the correct number on the form but when I click upload I get the "Aw Snap" screen:
Any idea why this is happening?
Besides Google Photos and the native app I tried 5 different apps, the last one, Piktures actually worked!
Please tell me this is not an app thing... is there a way to get the files correctly?
Code attached:
<form method="post" enctype="multipart/form-data">
<input type="file" name="my_file[]" multiple>
<input type="submit" value="Upload">
</form>
<?php
if (isset($_FILES['my_file'])) {
$myFile = $_FILES['my_file'];
$fileCount = count($myFile["name"]);
for ($i = 0; $i < $fileCount; $i++) {
?>
<p>File #<?= $i+1 ?>:</p>
<p>
Name: <?= $myFile["name"][$i] ?><br>
Temporary file: <?= $myFile["tmp_name"][$i] ?><br>
Type: <?= $myFile["type"][$i] ?><br>
Size: <?= $myFile["size"][$i] ?><br>
Error: <?= $myFile["error"][$i] ?><br>
</p>
<?php
}
}
?>
If you wish to test: http://odedta.com/projects/jqueryfileupload/
Thanks!
Try this might help you this is only front end part of file upload with js
window.onload = function() {
if (window.File && window.FileList && window.FileReader) {
var filesInput = document.getElementById("uploadImage");
filesInput.addEventListener("change", function(event) {
var files = event.target.files;
var output = document.getElementById("result");
for (var i = 0; i < files.length; i++) {
var file = files[i];
if (!file.type.match('image'))
continue;
var picReader = new FileReader();
picReader.addEventListener("load", function(event) {
var picFile = event.target;
var div = document.createElement("div");
div.innerHTML = "<img class='thumbnail' src='" + picFile.result + "'" +
"title='" + picFile.name + "'/>";
output.insertBefore(div, null);
});
picReader.readAsDataURL(file);
}
});
}
}
<input type="file" id="uploadImage" name="termek_file" class="file_input" multiple/>
<div id="result" class="uploadPreview">
I am not sure exactly about that mobile browsers are support multiple attribute I read some article it is not support or is not standart, any way If you want to post multiple image; You can see full code below
First Step;
You should use FileReader for load on browser as locally
Multiple file loading with FileReader
document.getElementById("filesToUpload").onchange = function () {
var fileIndex = 0;
for ( var x= 0; x < input.files.length; x++) {
//add to list
var li = document.createElement('li');
//Filename listing
li.setAttribute('id','li_'+x);
li.innerHTML = 'File ' + (x + 1) + ': ' + input.files[x].name;
list.append(li);
//FileReader create and set onload event
var reader = new FileReader();
reader.onload = function (data) {
data.target.result;
}
//Read file
reader.readAsDataURL(input.files[x]);
}
}
Second Step
You can set image content to textarea as base64 data for each file
reader.onload = function (data) {
//....
//Split base64 data from DataURL (// "data:image/png;base64,.....)
var b64 = data.target.result.split(',')[1];
var b64Input = document.createElement('textarea');
b64Input.setAttribute('name','file64[]');
b64Input.value = b64;
//...
}
Third Step
Then you can send to your php file whole data and save your content as image
for($i = 0; $i<count($_POST["fileName"]);$i++){
echo $_POST["fileName"][$i]."<br>";
//decode base64 content and put file
file_put_contents($_POST["fileName"][$i], base64_decode($_POST["file64"][$i]));
}
Full Code
HTML & JavaScript
<input name="filesToUpload[]" id="filesToUpload" type="file" multiple />
<form method="post" action="multipleFileUpload.php" enctype="multipart/form-data" id="formMultipleFileUpload">
<ul id="fileList">
</ul>
<input type="submit" value="Upload" id="btnUpload">
</form>
<script type="text/javascript">
var input = document.getElementById('filesToUpload');
var list = document.getElementById('fileList');
document.getElementById("filesToUpload").onchange = function () {
var fileIndex = 0;
for ( var x= 0; x < input.files.length; x++) {
//add to list
var li = document.createElement('li');
li.setAttribute('id','li_'+x);
li.innerHTML = 'File ' + (x + 1) + ': ' + input.files[x].name;
list.append(li);
var reader = new FileReader();
reader.onload = function (data) {
var li = document.getElementById('li_'+fileIndex);
var previewImg = document.createElement('img');
previewImg.setAttribute('width','50');
previewImg.setAttribute('height','50');
li.append(previewImg);
previewImg.src = data.target.result;
var b64 = data.target.result.split(',')[1];
var b64Input = document.createElement('textarea');
b64Input.setAttribute('name','file64[]');
b64Input.value = b64;
li.append(b64Input);
var fileName = document.createElement('input');
fileName.setAttribute('name','fileName[]');
fileName.value = input.files[fileIndex].name;
li.append(fileName);
fileIndex++;
}
reader.readAsDataURL(input.files[x]);
}
}
PHP (multipleFileUpload.php)
<?php
for($i = 0; $i<count($_POST["fileName"]);$i++){
echo $_POST["fileName"][$i]."<br>";
file_put_contents($_POST["fileName"][$i], base64_decode($_POST["file64"][$i]));
}
?>
Working screenshot
Hello!
I wrote the single java script function to show the image preview before uploading.
For single file uploading, my code is working fine.
But now i want to give multiple image uploading options by giving multiple select options to user(see the snapshot). Also for this, i want to reuse my function that is displaying the preview of selected first image.(see the image in snapshot)
How would i modify my html code and how to reuse my script function?
html
<form action="upload.php" method="post" enctype="multipart/form-data">
<div id="wrapper" style="margin-top: 20px;">
<input id="fileUpload" name="uploadedFile" type="file"/>
<input id="fileUpload2" name="" type="file"/>
<input id="fileUpload3" name="uploadedFile" type="file"/>
<div id="image-holder"></div>
</div>
</form>
Javascript
<script>
$(document).ready(function() {
$("#fileUpload").on('change', function() {
//Get count of selected files
var countFiles = $(this)[0].files.length;
var imgPath = $(this)[0].value;
var extn = imgPath.substring(imgPath.lastIndexOf('.') + 1).toLowerCase();
var image_holder = $("#image-holder");
image_holder.empty();
if (extn == "gif" || extn == "png" || extn == "jpg" || extn == "jpeg") {
if (typeof(FileReader) != "undefined") {
//loop for each file selected for uploaded.
for (var i = 0; i < countFiles; i++)
{
var reader = new FileReader();
reader.onload = function(e) {
$("<img />", {
"src": e.target.result,
"class": "thumb-image"
}).appendTo(image_holder);
}
image_holder.show();
reader.readAsDataURL($(this)[0].files[i]);
}
} else {
alert("This browser does not support FileReader.");
}
} else {
alert("Pls select only images");
}
});
});
</script>
This is what classes are for. You are only calling your jQuery on the fileUpload Id. And if your going to use the same image holder for more than one image like this you should not be clearing it out each time.
I refactored your code a small amount. Try this.
html
<form action="upload.php" method="post" enctype="multipart/form-data">
<div id="wrapper" style="margin-top: 20px;">
<input class="fileUploadClass" id="fileUpload" name="uploadedFile" type="file"/>
<input class="fileUploadClass" id="fileUpload2" name="" type="file"/>
<input class="fileUploadClass" id="fileUpload3" name="uploadedFile" type="file"/>
<div id="image-holder"></div>
</div>
JavaScript
<script>
$(document).ready(function() {
$(".fileUploadClass").on('change', function() {
//Get count of selected files
var countFiles = $(this)[0].files.length;
var imgPath = $(this)[0].value;
var extn = imgPath.substring(imgPath.lastIndexOf('.') + 1).toLowerCase();
var image_holder = $("#image-holder");
// image_holder.empty();
if (extn == "gif" || extn == "png" || extn == "jpg" || extn == "jpeg") {
if (typeof(FileReader) != "undefined") {
//loop for each file selected for uploaded.
for (var i = 0; i < countFiles; i++)
{
var reader = new FileReader();
reader.onload = function(e) {
$("<img />", {
"src": e.target.result,
"class": "thumb-image"
}).appendTo(image_holder);
}
image_holder.show();
reader.readAsDataURL($(this)[0].files[i]);
}
} else {
alert("This browser does not support FileReader.");
}
} else {
alert("Pls select only images");
}
});
});
I have a JavaScript function that shows me the previews of the images I want to upload to the server. After recieving that previews I can select some of them by clicking and remove previews, but I need also to remove the selected files so they will not be uploaded to the server.
The following code can remove the previews but not the files. How can it be improved?
JavaScript:
$(document).ready(function () {
$("#image-holder").on('click', '.thumb-image', function () {
$(this).toggleClass("selectedItem");
});
$("#btnDelete").on("click", function () {
$(".selectedItem").remove();
});
$("#fileUpload").on('change', function () {
//Get count of selected files
var countFiles = $(this)[0].files.length;
var imgPath = $(this)[0].value;
var extn = imgPath.substring(imgPath.lastIndexOf('.') + 1).toLowerCase();
var image_holder = $("#image-holder");
image_holder.empty();
if (extn == "gif" || extn == "png" || extn == "jpg" || extn == "jpeg") {
if (typeof(FileReader) != "undefined") {
//loop for each file selected for uploading.
for (var i = 0; i < countFiles; i++) {
var reader = new FileReader();
reader.onload = function (e) {
$("<img />", {
"src": e.target.result,
"class": "thumb-image"
}).appendTo(image_holder);
};
image_holder.show();
reader.readAsDataURL($(this)[0].files[i]);
}
} else {
alert("This browser does not support FileReader.");
}
} else {
alert("Please select only images");
}
});
});
HTML:
<form method="POST" action="upload" enctype="multipart/form-data">
<input id="fileUpload" name="file" multiple="multiple" type="file"/>
<br/>
<input type="submit" value="Upload">
</form>
<button id="btnDelete">Delete</button>
I've done this before using AngularJS. In that case I just had to set the ng-model variable to undefined. I haven't tested this, but you should be able to accomplish the same thing by clearing your <input> value in a similar way.
$("#btnDelete").on("click", function () {
$(".selectedItem").remove();
$("#fileUpload").get(0).files[0] = undefined;
$("#fileUpload").removeAttr('value');
});