Request uploaded image size with FILE API

select image file to upload, click on "Load" to see the message.

HTML

<h3>
Upload an image file.
</h3>
<h5>
(You will get a message if your image dimentions are larger than 200x200)    
</h5>
<form action='#' onsubmit="return false;">
    <input type='file' id='imgfile' />
    <input type='button' id='btnLoad' value='Load' />
</form>

CSS

body {
    font-family: sans-serif;
}

h5 {
    font-weight: normal;
}

JavaScript

$('#btnLoad').on('click', function () {

    loadImage();
});

function loadImage() {
    var input, file, fr, img;

    if (typeof window.FileReader !== 'function') {
        write("The file API isn't supported on this browser yet.");
        return;
    }

    input = document.getElementById('imgfile');
    if (!input) {
        write("Um, couldn't find the imgfile element.");
    } else if (!input.files) {
        write("This browser doesn't seem to support the `files` property of file inputs.");
    } else if (!input.files[0]) {
        write("Please select a file before clicking 'Load'");
    } else {
        file = input.files[0];
        fr = new FileReader();
        fr.onload = createImage;
        fr.readAsDataURL(file);
    }

    function createImage() {
        img = document.createElement('img');
        img.onload = imageLoaded;
        img.style.display = 'none'; // If you don't want it showing
        img.src = fr.result;
        document.body.appendChild(img);
    }

    function imageLoaded() {
        write("Your image dimentions are: " + img.width + "x" + img.height);
        if(img.width != 200){ write("width must be 200px")}
        if(img.height != 200){write("height must be 200px")}
       
        // This next bit removes the image, which is obviously optional -- perhaps you want
        // to do something with it!
        img.parentNode.removeChild(img);
        img = undefined;
    }

    function write(msg) {
        var p = document.createElement('p');
        p.innerHTML = msg;
        document.body.appendChild(p);
    }
}