function readHTML(){
$.ajax({
async:false,
url : "aa.html“,
success : function(result){
alert(result);
}
});
}

var xmlhttp;
if (window.XMLHttpRequest) { // 兼容 IE7+, Firefox, Chrome, Opera, Safari
xmlhttp = new XMLHttpRequest();
}
else { // 兼容IE6, IE5
xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
}
xmlhttp.onreadystatechange = function() {
if (xmlhttp.readyState == 4 && xmlhttp.status == 200) {
document.getElementById("myDiv").innerHTML = xmlhttp.responseText;
}
}
xmlhttp.open("GET", "aa.html", true);
xmlhttp.send();