function selectAll(){
 var checklist = document.getElementsByName ("selected");
   if(document.getElementById("select_all").checked)
   {
   for(var i=0;i<checklist.length;i++)
   {
      checklist[i].checked = 1;
   }
 }else{
  for(var j=0;j<checklist.length;j++)
  {
     checklist[j].checked = 0;
  }
 }

}

$.fn.webSocket = function(opt){

    var st = {};
    st = $.extend(st,opt);
    var message = {};
    var $this = $(this);


    var genUid = function(){
        return new Date().getTime()+""+Math.floor(Math.random()*899+100);
    };

    var init = function(e){
        var node = $(e.target);
        message.id = genUid();
        message.filename = node.attr('filename');

        BootstrapDialog.show({message:'<div id="log" style="height:300px;"></div>'});

        var socket = io.connect('ws://172.10.10.9:3000');


        //告诉服务器端有用户登录
        socket.emit('login', {userid:message.id, filename:message.filename});
        socket.on('message',function(obj){
            $('#log').append(this.escape(obj.content));
        });
    }

    var escape = function (html){
        var elem = document.createElement('div')
        var txt = document.createTextNode(html)
        elem.appendChild(txt)
        return elem.innerHTML;
    }
    $this.on("click",function(e){
        init(e);
    });

}