getElementById.contentDocument error in IE

Answer 1

Use feature detection, as contentDocument is supported in IE 8:

var iframe = document.getElementById("iView");
var iframeDocument = null;
if (iframe.contentDocument) {
    iframeDocument = iframe.contentDocument;
} else if (iframe.contentWindow) {
    // for IE 5.5, 6 and 7:
    iframeDocument = iframe.contentWindow.document;
}
if (!!iframeDocument) {
    // do things with the iframe's document object
} else {
    // this browser doesn't seem to support the iframe document object
}