nodejs实现的一个简单聊天室功能分享(2)

var ws = io.connect('http://172.16.2.184:8888');
          var sendMsg = function(msg){
              ws.emit('send.message', msg);
          }
          var addMessage = function(from, msg){
              var li = document.createElement('li');
              li.innerHTML = '<span>' + from + '</span>' + ' : ' + msg;
              document.querySelector('#chat_conatiner').appendChild(li);

// 设置内容区的滚动条到底部
              document.querySelector('#chat').scrollTop = document.querySelector('#chat').scrollHeight;

// 并设置焦点
              document.querySelector('textarea').focus();

}

var send = function(){
              var ele_msg = document.querySelector('textarea');
              var msg = ele_msg.value.replace('\r\n', '').trim();
              console.log(msg);
              if(!msg) return;
              sendMsg(msg);
              // 添加消息到自己的内容区
              addMessage('你', msg);
              ele_msg.value = '';
          }

ws.on('connect', function(){
              var nickname = window.prompt('输入你的昵称!');
              while(!nickname){
                  nickname = window.prompt('昵称不能为空，请重新输入!')
              }
              ws.emit('join', nickname);
          });

// 昵称有重复
          ws.on('nickname', function(){
              var nickname = window.prompt('昵称有重复，请重新输入!');
              while(!nickname){
                  nickname = window.prompt('昵称不能为空，请重新输入!')
              }
              ws.emit('join', nickname);
          });

ws.on('send.message', function(from, msg){
              addMessage(from, msg);
          });

ws.on('announcement', function(from, msg){
              addMessage(from, msg);
          });

document.querySelector('textarea').addEventListener('keypress', function(event){
              if(event.which == 13){
                  send();
              }
          });
          document.querySelector('textarea').addEventListener('keydown', function(event){
              if(event.which == 13){
                  send();
              }
          });
          document.querySelector('#send').addEventListener('click', function(){
              send();
          });