z作业留言的字数控制

app/views/homework_attach/_addjour.html.erb

@@ -69,7 +69,9 @@
 
     <% if User.current.logged? %>
         <%= f.text_area 'user_message', :rows => 3, :cols => 65,
-                     :style => "resize: none;", :class => 'noline', :placeholder => l(:text_caracters_maximum,:count=>250)%>
+                     :style => "resize: none;", :class => 'noline', :placeholder => l(:text_caracters_maximum,:count=>250),
+                     :maxlength => 250
+        %>
         <%= f.text_field :reference_user_id, :style=>"display:none"%>
         <div style="float:right">
           <a href="#" class="ping_sub1" id="jours_submit" onclick="submit1();"><%= l(:label_submit_comments) %></a>

app/views/homework_attach/_show.html.erb

@@ -1,6 +1,42 @@
 <% reply_allow = JournalsForMessage.create_by_user? User.current %>
 
+
 <script type="text/javascript" language="javascript">
+    var W3CDOM = document.createElement && document.getElementsByTagName;
+
+//    window.onload = setMaxLength;
+    $(document).ready(setMaxLength());
+    function setMaxLength() {
+        if (!W3CDOM) return;
+        var textareas = document.getElementsByTagName('textarea');
+        for (var i=0;i<textareas.length;i++) {
+            var textarea = textareas[i];
+            setMaxLengthItem(textareas[i]);
+        }
+    }
+    function setMaxLengthItem(textarea){
+        if (textarea.getAttribute('maxlength')) {
+            var counter = document.createElement('div');
+            counter.className = 'counter';
+            var counterClone = counter.cloneNode(true);
+            counterClone.innerHTML = '<span>0</span>/'+textarea.getAttribute('maxlength');
+            textarea.parentNode.insertBefore(counterClone,textarea.nextSibling);
+            textarea.relatedElement = counterClone.getElementsByTagName('span')[0];
+            textarea.onkeyup = textarea.onchange = checkMaxLength;
+            textarea.onkeyup();
+        }
+    }
+
+    function checkMaxLength() {
+        var maxLength = this.getAttribute('maxlength');
+        var currentLength = this.value.length;
+        if (currentLength > maxLength)
+            this.relatedElement.className = 'toomuch';
+        else
+            this.relatedElement.className = '';
+        this.relatedElement.firstChild.nodeValue = currentLength;
+    }
+    function test(){alert('test');}
       //<!CDATA[
       function g(o){return document.getElementById(o);}
       function HoverLi(n){