AJAX動的取得現在時刻(php)

クライアントコード:

 
  
 
  
 
  
 
  
 
  
 
  
 
  
 
  <br>var xmlHttp; 
  <br>function createXMLHttpRequest(){ 
  <br>if(window.ActiveXObject){ 
  <br>xmlHttp = new ActiveXObject("microsoft.XMLHTTP"); 
  <br>} 
  <br>else if(window.XMLHttpRequest){ 
  <br>xmlHttp = new XMLHttpRequest(); 
  <br>} 
  <br>else{ 
  <br>alert("      "); 
  <br>} 
  <br>} 
  <br>function sendRequest(){ 
  <br>createXMLHttpRequest(); 
  <br>url = "time_check.php"; 
  <br>xmlHttp.onreadystatechange = callback; 
  <br>xmlHttp.open('GET',url,true); 
  <br>xmlHttp.send(null); 
  <br>} 
  <br>function callback(){ 
  <br>if(xmlHttp.readyState ==4){ 
  <br>if(xmlHttp.status == 200){ 
  <br>document.getElementById("time").innerHTML = xmlHttp.responseText; 
  <br>setTimeout("sendRequest()",1000); 
  <br>} 
  <br>} 
  <br>} 
  <br> 
  
 
  
 
  

 
  
 
  
 
  
 
  
 
 

サーバ側コード:

 
  
header("cache-control:no-cache,must-revalidate"); //  php        
  
header('Content-type: text/html;charset=GB2312'); 
  
$showtime = date("    Y m d H:i:s"); 
  
echo $showtime; 
  
?>