fix: replace struts tag forms in learning pages

web/WEB-INF/views/upload/index.jsp

@@ -102,22 +102,22 @@
             </div>
 
             <s:if test="hasActionErrors()">
-                <div class="action-error"><s:actionerror/></div>
+                <div class="action-error"><s:property value="actionErrors[0]"/></div>
             </s:if>
 
-            <s:form action="upload" method="post" enctype="multipart/form-data" namespace="/">
+            <form action="<s:url action='upload' namespace='/'/>" method="post" enctype="multipart/form-data">
                 <div class="field">
-                    <label>主文件</label>
-                    <s:file name="upload"/>
+                    <label for="upload">主文件</label>
+                    <input id="upload" type="file" name="upload"/>
                 </div>
 
                 <div class="field">
-                    <label>附加文件</label>
-                    <s:file name="uploads" multiple="multiple"/>
+                    <label for="uploads">附加文件</label>
+                    <input id="uploads" type="file" name="uploads" multiple="multiple"/>
                 </div>
 
                 <button type="submit">提交并查看上传元数据</button>
-            </s:form>
+            </form>
 
             <div class="links">
                 <a class="link-btn" href="../dashboard.action">返回仪表盘</a>