全网页截图工具

<script type="text/javascript" src="http://html2canvas.hertzen.com/dist/html2canvas.js"></script>
    <script>
        document.querySelector(‘.btn‘).onclick=function(event) {
            event.preventDefault();
            html2canvas(document.body).then(function(canvas) {
                var dataUrl = canvas.toDataURL();
                var newImg = document.createElement("img");
                newImg.src =  dataUrl;
                document.body.appendChild(newImg);
            });   
        }