新建pull request的时候JS控制标题不能为空

app/views/pull_requests/_form.html.erb

@@ -1,7 +1,7 @@
 <%= form_tag(url_for(:controller => 'pull_requests', :action => 'create', :project_id => @project.id), :id => 'pull_request_form', :method => "post", :remote => true) do %>
     <div class="new-merge-wrap">
-      <div class="merge-option-name fl mt8">标题</div><input type="text" name="title" class="merge-title-input fl ml30" />
-      <!--<p class="fl ml100 fontGrey2 mt5">标题以<span class="c_red">[WIP]</span>或<span class="c_red">WIP</span>开头：以防还在进程中的合并请求在它完成之前被合并</p>-->
+      <div class="merge-option-name fl mt8">标题</div><input type="text" id="pr_name" name="title" class="merge-title-input fl ml30" />
+      <p id ="pull_request_title" class="fl ml100 fontGrey2 mt5 c_red" style="display: none">标题不能为空</p>
       <div class="cl mb10"></div>
       <div class="merge-option-name fl">描述</div><textarea type="text" name="description" class="merge-description-input fl ml30"></textarea>
       <!--<p class="fl ml100 f12 mt5"><a href="javascript:void(0);" class="AnnexBtn fl mr10">上传附件</a></p>-->
@@ -20,8 +20,34 @@
       <div class="cl"></div>
     </div>
     <div class="new-merge-row b_grey" style="border-top:1px solid #ddd;">
-      <a href="javascript:void(0);" class="BlueCirBtn fl ml10" onclick="$('#pull_request_form').submit()">提交请求</a>
+      <a href="javascript:void(0);" class="BlueCirBtn fl ml10" onclick="pull_request_commit()">提交请求</a>
       <%= link_to "返回", project_pull_requests_path(:project_id => @project.id), :class => "fr linkGrey2 mt5 mr10" %>
       <div class="cl"></div>
     </div>
 <% end %>
+
+<script>
+    function regex_pr_name()
+    {
+        var name = $.trim($("#pr_name").val());
+        if(name.length == 0)
+        {
+            $("#pull_request_title").show();
+            return false;
+        }
+        else
+        {
+            $("#pull_request_title").hide();
+            return true;
+        }
+    }
+
+    //提交pull request
+    function pull_request_commit()
+    {
+        if(regex_pr_name())
+        {
+            $("#pull_request_form").submit();
+        }
+    }
+</script>