//get username
 function getUsername(){
 blackScreen.fadeOut("slow");
 return $("#input-username").val();
 }
 okay.click(getUsername);
 //send msg to database by enter
 formUsername.keypress(function(event) {
 if(event.keyCode === 13) {
 event.preventDefault();
 okay.trigger("click");
 }
 });
 
 //get time
 function getTime() {
 var mydate = new Date();
 var year = mydate.getFullYear();
 var month = mydate.getMonth() + 1;
 var day = mydate.getDate();
 var hour = mydate.getHours();
 var minute = mydate.getMinutes();
 var second = mydate.getSeconds();
 //standardize time
 function stdTime(s) {
 if(s < 10) {
 return "0" + s;
 } else {
 return s;
 }
 };
 return year + "/" + stdTime(month) + "/" + stdTime(day) + " " + stdTime(hour) + ":" + stdTime(minute) + ":" + stdTime(second);
 }

 //send msg to database by click
 inputBtn.click(function() {

 var inputMsg = $("#input-value").val();

 //push msg to database
 msgs.push({
 "name": getUsername(),
 "time": getTime(),
 "msg": inputMsg
 });
 $("#input-value").val("");

 });

 //send msg to database by enter
 inputForm.keypress(function(event) {
 if(event.keyCode === 13) {
 event.preventDefault();
 inputBtn.trigger("click");
 }
 });

<div class="chat-room-input">
 <form class="form-inline form-input">
 <div class="form-group">
 <input type="text" class="form-control" id="input-value" placeholder="來一起吐槽~" maxlength="80">
 <button type="button" class="btn btn-default" id="input-send">
 <span class="glyphicon glyphicon-send" aria-hidden="true"></span>
 </button>
 </div>
 </form>
 </div>


<div class="alert alert-warning alert-dismissible" role="alert">
 <form class="form-inline form-username">
 <div class="form-group">
 <input type="text" class="form-control" id="input-username" placeholder="騷年！留下大名！" maxlength="10" autofocus="autofocus">
 <button type="button" class="btn btn-default okay">OK</button>
 </div>
 </form>
 </div>

formUsername.keypress(function(event) { if(event.keyCode === 13) { event.preventDefault();
 okay.trigger("click");
 } event.stopImmediatePropagation();
 });

 formUsername.keypress(function(event) { event.stopPropagation(); //防止事件冒泡
 if(event.keyCode === 13) { event.preventDefault();
 okay.trigger("click");
 }
 });
 inputForm.keypress(function(event) { event.stopPropagation();//防止事件冒泡
 if(event.keyCode === 13) { event.preventDefault();
 inputBtn.trigger("click");
 }
 });