Question

这是我的代码，我得到一个错误，任何人都可以告诉我原因是什么？

  <s:select label="Index" name="index" list="%{#{}}">
     <s:iterator value="#session.subscription_countries" var="slist">
         <s:property/>
    <s:if test='#slist=="CANADA" || #slist=="ALL"'>
    <s:optgroup label="Canada" list="%{#{'TSX':'TSX'}}" />
    </s:if>
    <s:if test='#slist=="UK" || #slist=="ALL"'>
    <s:optgroup label="United Kingdom" list="%{#{'FTSE100':'FTSE100'}}" />
    </s:if>
    <s:if test='#slist=="USA" || #slist=="ALL"'>
    <s:optgroup label="USA" list="%{#{'S&P500':'S&P500'}" />
    </s:if>
    <s:if test='#slist=="INDIA" || #slist=="ALL"'>
    <s:optgroup label="India" list="%{#{'NIFTY':'NIFTY','CNX100':'CNX100'}}" />
    </s:if>
     </s:iterator>

    </s:select>

错误

程序员的Java回溯：

freemarker.core.InvalidReferenceException: Expression optGroupInternalListUiBean.parameters.list is undefined on line 36, column 8 in template/simple/optgroup.ftl.
    at freemarker.core.TemplateObject.assertNonNull(TemplateObject.java:124)
    at freemarker.core.IteratorBlock.accept(IteratorBlock.java:100)
    at freemarker.core.Environment.visit(Environment.java:209)
    at freemarker.core.MixedContent.accept(MixedContent.java:92)
    at freemarker.core.Environment.visit(Environment.java:209)
    at freemarker.core.IteratorBlock$Context.runLoop(IteratorBlock.java:167)
    at freemarker.core.Environment.visit(Environment.java:416)
    at freemarker.core.IteratorBlock.accept(IteratorBlock.java:102)
    at freemarker.core.Environment.visit(Environment.java:209)
    at freemarker.core.MixedContent.accept(MixedContent.java:92)
    at freemarker.core.Environment.visit(Environment.java:209)
    at freemarker.core.ConditionalBlock.accept(ConditionalBlock.java:79)
    at freemarker.core.Environment.visit(Environment.java:209)
    at freemarker.core.MixedContent.accept(MixedContent.java:92)
    at freemarker.core.Environment.visit(Environment.java:209)
    at freemarker.core.Environment.include(Environment.java:1482)
    at freemarker.core.Include.accept(Include.java:169)
    at freemarker.core.Environment.visit(Environment.java:209)
    at freemarker.core.MixedContent.accept(MixedContent.java:92)
    at freemarker.core.Environment.visit(Environment.java:209)
    at freemarker.core.Environment.include(Environment.java:1482)
    at freemarker.core.Include.accept(Include.java:169)
    at freemarker.core.Environment.visit(Environment.java:209)
    at freemarker.core.MixedContent.accept(MixedContent.java:92)
    at freemarker.core.Environment.visit(Environment.java:209

Answer 1

根据我的理解，你试图从会话中获取列表并将其迭代到框中，如果我是对的，那么你可以试试这个。

“listValue =” 这里 1.list是列表的名称 2.headerKey / headerValue - 没有必要但如果你添加它，它们将出现在你选择框的顶部 3. listKey： - 它将成为你的页面，并且是列表中的类，value是类中的变量，具有值。 4. listValue： - 与listKey相同

如果listKey / listValue是字符串对象，则写入而不是

我希望这会有所帮助感谢

尝试在Struts 2中显示数组列表并收到错误

程序员的Java回溯：

1 个答案: