无法使用Struts2拦截器验证图像上传表单

Question

i am trying to put validation into my image upload form using struts2 interceptor if users submits invalid image extension there there should be validation error message?

uploadThemeImage.jsp

<s:form action="updatethemeimageform"  method="post" enctype="multipart/form-data" id="remoteform"  theme="simple" >
     <s:hidden value="%{#parameters.themeid}" name="themId"/>  
      <s:file name="thempic" label="Theme Screenshot" /> 
      <sj:a button="true" id="btnsid" buttonIcon="ui-icon-gear" dataType="json" indicator="indicator"  onSuccessTopics="reloadMyGrid,handleJsonResult"  
        formIds="remoteform" targets="result">Submit This Form</sj:a>  </s:form>

Answer 1

You can't see the error if you don't put an <s:fielderror /> tag in your JSP.

Add it before <s:form> and you will see your validation error...

PS: the same applies to <s:actionmessage /> and <s:actionerror > (that are not involved with the validation but added by you)