How to open a file / browse dialog using javascript?
Is there any way to open the browse for files dialog box when a <a href>
link is clicked using javascript? It should function like a normal browse for files button and give the names/list of files selected i开发者_开发百科n response.
Here is a non-jQuery solution. Note you can't just use .click()
as some browsers do not support it.
<script type="text/javascript">
function performClick(elemId) {
var elem = document.getElementById(elemId);
if(elem && document.createEvent) {
var evt = document.createEvent("MouseEvents");
evt.initEvent("click", true, false);
elem.dispatchEvent(evt);
}
}
</script>
<a href="#" onclick="performClick('theFile');">Open file dialog</a>
<input type="file" id="theFile" />
Use this.
<script>
function openFileOption()
{
document.getElementById("file1").click();
}
</script>
<input type="file" id="file1" style="display:none">
<a href="#" onclick="openFileOption();return;">open File Dialog</a>
Create input element.
Missing from these answers is how to get a file dialog without a input element on the page.
The function to show the input file dialog.
function openFileDialog (accept, callback) { // this function must be called from a user
// activation event (ie an onclick event)
// Create an input element
var inputElement = document.createElement("input");
// Set its type to file
inputElement.type = "file";
// Set accept to the file types you want the user to select.
// Include both the file extension and the mime type
inputElement.accept = accept;
// set onchange event to call callback when user has selected file
inputElement.addEventListener("change", callback)
// dispatch a click event to open the file dialog
inputElement.dispatchEvent(new MouseEvent("click"));
}
NOTE the function must be part of a user activation such as a click event. Attempting to open the file dialog without user activation will fail.
NOTE
input.accept
is not used in Edge
Example.
Calling above function when user clicks an anchor element.
// wait for window to load
window.addEventListener("load", windowLoad);
// open a dialog function
function openFileDialog (accept, multy = false, callback) {
var inputElement = document.createElement("input");
inputElement.type = "file";
inputElement.accept = accept; // Note Edge does not support this attribute
if (multy) {
inputElement.multiple = multy;
}
if (typeof callback === "function") {
inputElement.addEventListener("change", callback);
}
inputElement.dispatchEvent(new MouseEvent("click"));
}
// onload event
function windowLoad () {
// add user click event to userbutton
userButton.addEventListener("click", openDialogClick);
}
// userButton click event
function openDialogClick () {
// open file dialog for text files
openFileDialog(".txt,text/plain", true, fileDialogChanged);
}
// file dialog onchange event handler
function fileDialogChanged (event) {
[...this.files].forEach(file => {
var div = document.createElement("div");
div.className = "fileList common";
div.textContent = file.name;
userSelectedFiles.appendChild(div);
});
}
.common {
font-family: sans-serif;
padding: 2px;
margin : 2px;
border-radius: 4px;
}
.fileList {
background: #229;
color: white;
}
#userButton {
background: #999;
color: #000;
width: 8em;
text-align: center;
cursor: pointer;
}
#userButton:hover {
background : #4A4;
color : white;
}
<a id = "userButton" class = "common" title = "Click to open file selection dialog">Open file dialog</a>
<div id = "userSelectedFiles" class = "common"></div>
Warning the above snippet is written in ES6.
Unfortunately, there isn't a good way to browse for files with a JavaScript API. Fortunately, it's easy to create a file input in JavaScript, bind an event handler to its change
event, and simulate a user clicking on it. We can do this without modifications to the page itself:
$('<input type="file" multiple>').on('change', function () {
console.log(this.files);
}).click();
this.files
on the second line is an array that contains filename, timestamps, size, and type.
Here's is a way of doing it without any Javascript and it's also compatible with any browser.
EDIT: In Safari, the input
gets disabled when hidden with display: none
. A better approach would be to use position: fixed; top: -100em
.
<label>
Open file dialog
<input type="file" style="position: fixed; top: -100em">
</label>
Also, if you prefer you can go the "correct way" by using for
in the label
pointing to the id
of the input like this:
<label for="inputId">file dialog</label>
<input id="inputId" type="file" style="position: fixed; top: -100em">
you can't use input.click()
directly, but you can call this in other element click event.
html
<input type="file">
<button>Select file</button>
js
var botton = document.querySelector('button');
var input = document.querySelector('input');
botton.addEventListener('click', function (e) {
input.click();
});
this tell you Using hidden file input elements using the click() method
I worked it around through this "hiding" div ...
<div STYLE="position:absolute;display:none;"><INPUT type='file' id='file1' name='files[]'></div>
How about make clicking the a tag, to click on the file button?
There is more browser support for this, but I use ES6, so if you really want to make it work in older and any browser, try to transpile it using babel, or just simply use ES5:
const aTag = document.getElementById("open-file-uploader");
const fileInput = document.getElementById("input-button");
aTag.addEventListener("click", () => fileInput.click());
#input-button {
position: abosulte;
width: 1px;
height: 1px;
clip: rect(1px 1px 1px 1px);
clip: rect(1px, 1px, 1px, 1px);
}
<a href="#" id="open-file-uploader">Open file uploader</a>
<input type="file" id="input-button" />
I know this is an old post, but another simple option is using the INPUT TYPE="FILE" tag according to compatibility most major browser support this feature.
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