PHP中遇到AJAX的有关问题

PHP中遇到AJAX的问题

header("Content-Type:html/text;Charset=utf-8");

$name = $_POST['name'];

$email = $_POST['email'];

$comment = $_POST['comment'];

$fh = @fopen("14-6.txt","ab");

fwrite($fh,"姓名:".$name,strlen($name));

fwrite($fh,"email:".$email,strlen($email));

fwrite($fh,"评论:".$comment,strlen($comment));

fclose($fh);

echo 1;

?>

function $(id){

	return document.getElementById(id);

}

function addcomment(){

	var url = "14-6.php";

	var status = document.getElementById("divmsg");

	status.value="正在提交》》》";

	var param = "name="+$("name").value+"email="+$("email").value+"comment="+$("comment").value;

	xmlhttp_request.onreadystatechange = function(){

		if(xmlhttp_request.readyState==4 && xmlhttp_request.status == 200){//相应完全显示信息

			alert (xmlhttp_request.responseText);

			if(xmlhttp_request.responseText == "1"){

				status.value = "发表成功！！";

				$("name").value="";

				$("email").value="";

				$("comment").value="";

			}else{

				status.value = "发表失败！请重新发表！";

			}

		}	

	}

	xmlhttp_request.open("POST",url,true);

	xmlhttp_request.setRequestHeader("Content-Type","application/x-www-form-urlencoded");//设置头信息

	xmlhttp_request.send(param);

}