[devote]

var url = "url.txt"
iframe = document.createElement('iframe');
iframe.setAttribute('src', url);
iframe.setAttribute('id', 'iframe');
iframe.style.width = 640+'px';
iframe.style.height = 480+'px';
iframe.contentWindow.onload = function() {
    alert( iframe.contentWindow.document.body.innerHTML );
}
document.body.appendChild(iframe);