<div id="result"></div> 
<textarea name="msg" id="msg" placeholder="输入内容" autofocus></textarea> 
<button type="submit">提 交</button><span>可按“Ctrl+Enter”键提交</span> 

textarea {display:block; width:450px;height:100px;border: 1px solid #ccc;} 
button {border: 1px solid #ccc; background: #ececec;-webkit-border-radius: 3px; 
-moz-border-radius: 3px;margin-top: 10px;padding: 5px 20px; cursor:pointer} 
.post{width: 230px;border: 1px solid #ccc;background: #ececec; padding: 10px; margin: 10px 0;} 

<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.8.2/jquery.min.js"></script> 

$.fn.ctrlEnter = function (btns, fn) { 
   var thiz = $(this); 
   btns = $(btns); 
     
   function performAction (e) { 
     fn.call(thiz, e); 
   }; 
   thiz.bind("keydown", function (e) { 
    if (e.keyCode === 13 && e.ctrlKey) { 
      performAction(e); 
      e.preventDefault(); //阻止默认回车换行 
    } 
   }); 
   btns.bind("click", performAction); 
} 

$("#msg").ctrlEnter("button", function () { 
    $("<p class='post'></p>").append(this.val().replace(/\n/g, "<br/>")).fadeIn('slow') 
.appendTo("#result"); 
    this.val(""); 
});