var xmlHttp;
function creatXMLHttpRequest() {
    if(window.ActiveXObject) {
        xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
    } else if(window.XMLHttpRequest) {
        xmlHttp = new XMLHttpRequest();
    }
}

//POST方式提交
function startRequest() {
    var queryString;
    var domain = document.getElementById("domain").value;
    queryString = "domain=" + domain;
    creatXMLHttpRequest();
    xmlHttp.open("POST","url.php","true");
    xmlHttp.onreadystatechange = handleStateChange;
    xmlHttp.setRequestHeader("Content-Type","application/x-www-form-urlencoded;");
    xmlHttp.send(queryString);
}

//GET方式提交
function startRequest() {
    var url = "test.php?a=1&b=2&c=3";
    creatXMLHttpRequest();
    xmlHttp.open("GET",url,"true");
    xmlHttp.onreadystatechange = handleStateChange;
    xmlHttp.setRequestHeader("Content-Type","application/x-www-form-urlencoded;");
    xmlHttp.send(null);
}

function handleStateChange() {
    if(xmlHttp.readyState == 1) {
        document.getElementById("result").style.cssText = "";
        document.getElementById("result").innerHTML = "<div align="center">Loading...</div>";
    }
    if(xmlHttp.readyState == 4) {
        if(xmlHttp.status == 200) {
            document.getElementById("result").style.cssText = "";
            var allcon =  xmlHttp.responseText;
            document.getElementById("result").innerHTML = allcon;
        }
    }
}