PHP+jquery+ajax实现即时聊天功能实例，jqueryajax_PHP教程

<script> <br /> var chat = { <br /> init:function(){ <br /> chat.first(); <br /> $('#chat_btn').unbind('click').click(function(){ <br /> chat.send(); <br /> }); <br /> $('#my_chat').keyup(function(){ <br /> if(event.keyCode == 13){ <br /> chat.send(); <br /> } <br /> });<br /> }, <br /> first:function(){ <br /> $.getJSON('data.php',{ <br /> action:'first', <br /> type:'l' <br /> },function(data){ <br /> chat.btn_status._true(); <br /> $('#mwebtime').html(data.time); <br /> $('#chat textarea').val(data.chat); <br /> $('#chat textarea').stop(true,true).animate({scrollTop:9999}, 1); <br /> chat.socket(); <br /> }); <br /> }, <br /> send:function(){ <br /> chat.btn_status._false(); <br /> $.getJSON('send.php',{ <br /> txt:$('#my_chat').val(), <br /> type:'l' <br /> },function(data){ <br /> if(data.status==200){ <br /> chat.btn_status._false(); <br /> $('#my_chat').val(''); <br /> setTimeout(function(){ <br /> chat.btn_status._true(); <br /> },2000); <br /> } <br /> }); <br /> }, <br /> socket:function(){ <br /> $.getJSON('data.php',{ <br /> action:'while', <br /> type:'l' <br /> },function(data){ <br /> $('#mwebtime').html(data.time); <br /> $('#chat textarea').val(data.chat); <br /> $('#chat textarea').stop(true,true).animate({scrollTop:9999}, 1); <br /> chat.socket(); <br /> }); <br /> }, <br /> btn_status:{ <br /> _false:function(){ <br /> $('#chat_btn').html('等待').attr('disabled',true); <br /> }, <br /> _true:function(){ <br /> $('#chat_btn').html('发言').attr('disabled',false); <br /> } <br /> } <br /> } <br /> chat.init(); <br /> </script>

 

header("Expires: Mon, 26 Jul 1997 05:00:00 GMT"); 
header("Last-Modified: ".gmdate("D, d M Y H:i:s")." GMT"); 
header("Cache-Control: no-cache, must-revalidate"); 
header("Pramga: no-cache");
set_time_limit(0);
$get = $_GET['action'];
$type = $_GET['type'];
$file = $type.'.txt';
if(isset($get) && isset($type) && file_exists($file)){
 switch($get){
  case 'first':
   $chat = file_get_contents($file);
   $json=array(
    'status' => 200,
    'time' => gmdate("s"),
    'chat' => $chat,
   );
   echo json_encode($json);
   break;
  case 'while':
   $oldsize = filesize($file);
   $newsize = filesize($file);
   while(true){
    if($oldsize!=$newsize){
     $chat = file_get_contents($file);
     $json=array(
      'status' => 200,
      'time' => gmdate("s"),
      'chat' => $chat,
     );
     echo json_encode($json);
     exit;
    }
    clearstatcache();
    $newsize = filesize($file);
    usleep(10000);
   }
   break;
 }
}
?>

$json = array();
$txt = isset($_GET['txt'])?$_GET['txt']:'';
$type = isset($_GET['type'])?$_GET['type']:'';
if($txt!=''){
 $file = $type.".txt";
 if(file_exists($file)){
  $fp = fopen($file,"a");
  $str = "rn".'Admin：'.$txt;
  //$str = $txt."n"//linux;
  fwrite($fp, $str);
  fclose($fp);
  $json['status']=200;
  echo json_encode($json);
  exit;
 }
}
?>