How to determine if user selected a file for file upload?

JavascriptHtmlUpload

Javascript Problem Overview

If I have a

<input id="uploadFile" type="file" />

tag, and a submit button, how do I determine, in IE6 (and above) if a file has been selected by the user.

In FF, I just do:

var selected = document.getElementById("uploadBox").files.length > 0;

But that doesn't work in IE.

Javascript Solutions

Solution 1 - Javascript

This works in IE (and FF, I believe):

if(document.getElementById("uploadBox").value != "") {
   // you have a file
}

Solution 2 - Javascript

this piece of code works in my local environment, hope it will also works in live

var nme = document.getElementById("uploadFile");
if(nme.value.length < 4) {
    alert('Must Select any of your photo for upload!');
    nme.focus();
    return false;
}

Solution 3 - Javascript

function validateAndUpload(input){
    var URL = window.URL || window.webkitURL;
    var file = input.files[0];

    if (file) {
        var image = new Image();

        image.onload = function() {
            if (this.width) {
                 console.log('Image has width, I think it is real image');
                 //TODO: upload to backend
            }
        };

        image.src = URL.createObjectURL(file);
    }
};​

<input type="file" name="uploadPicture" accept="image/*" onChange="validateAndUpload(this);"/>

Call this function on change .

Solution 4 - Javascript

You can use:

	var files = uploadFile.files;

	if (files.length == 0) { console.log(true) } else { console.log(false) }
	if (files[0] == undefined) { console.log(true) } else { console.log(false) }
	if (files[0] == null) { console.log(true) } else { console.log(false) }

All three give the same result.

Solution 5 - Javascript

You can check it in asp.net using c#:

html:

<input id="FileID" runat="server" type="file"/>

c#:

if(FileID.PostedFile.FileName != "")
{
    // do whatever you want if file is selected
}
else
{
    //do whatever you want if no file is selected
}
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Attributions

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Content TypeOriginal AuthorOriginal Content on Stackoverflow
QuestionslolifeView Question on Stackoverflow
Solution 1 - JavascriptJason BuntingView Answer on Stackoverflow
Solution 2 - JavascriptAtiqurView Answer on Stackoverflow
Solution 3 - JavascriptAshuView Answer on Stackoverflow
Solution 4 - JavascriptElion LimanajView Answer on Stackoverflow
Solution 5 - JavascriptHibaHasanView Answer on Stackoverflow