How to check input file is empty, and also display an alert if png format is selected using jquery

Question

I have got an input file upload , need to check which file is uploaded / if no file is selected by the client using jquery.

Answer 1

Testing for...

$('#file1')[0].files.length == 0

...is working for me in Chrome. The jQuery is actually not even necessary as the raw HTML element (returned by the [0] on the jQuery object) gives access to the files list.

Answer 2

Have you made any attempt at doing this?

$('input[type="file"]').val()

Answer 3

See the sample I have created:

http://jsfiddle.net/G7xke/

---

<form>
<input type="file" name="files" id="file1" style="color:White" />
<input type="submit" value="Create" />
</form>
<button value="check" id="check" name="check" >check</button>

And JavaScript:

$("#check").click(function(){
    var fileName = $("#file1").val();
    if(fileName.lastIndexOf("png")===fileName.length-3)
        alert("OK");
    else
        alert("Not PNG");
})

Answer 4

This demo works in IE9 + Chrome:

http://jsfiddle.net/brdFq/

using Jquery, you get the val();

a quick implementation here:

function hasFile(selector){
    //if there is a value, return true, else: false;
    return $(selector).val()? true: false;
}