function createAjax(){
var http;
if (window.ActiveXObject){
    http=new ActiveXObject(”Microsoft.XMLHTTP”) ? new ActiveXObject(”Microsoft.XMLHTTP”) : new ActiveXObject(”Msxml2.XMLHTTP”);
}
else if(window.XMLHttpRequest)
{
    http=new XMLHttpRequest();
}
return http;
}
var ajax=createAjax();
function show(){//ajax乱码是因为在传递中文的时候没有进行编码，escape（）是进行编码。
ajax.open(”GET”,”a.asp?text=”+escape(document.getElementById(”text”).value)+”&num=”+Math.random(),true);
ajax.send(null);
ajax.onreadystatechange=getmessage;
}

function getmessage(){
var html;
if (ajax.readyState==4){
        if (ajax.status==200){
        html=ajax.responseText;
        document.getElementById(”showinfo”).innerHTML=html;
        }else    alert(’status is:’+ajax.status);

}else{
document.getElementById(”showinfo”).innerHTML=”数据读取中…”;
}
}
</script>