Input file type selected file chek extension

Input file type selected file chek extension

by Ankit Patidar

HTML

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

JavaScript

var fl = document.getElementById('f');

fl.onchange = function(e){ 
    var ext = this.value.match(/\.(.+)$/)[1];
    switch(ext)
    {
        case 'jpg':
        case 'bmp':
        case 'png':
        case 'tif':
            alert('allowed');
            break;
        default:
            alert('not allowed');
            this.value='';
    }
};