javascript Struts 2 s:select 标签动态id
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Struts 2 s:select tag dynamic id
提问by Rohit Ramkumar
I have multiple fields of various types in a JSP page and one button. These fields are generated based on the info got from a metadata table that I have created.
我在一个 JSP 页面和一个按钮中有多个不同类型的字段。这些字段是根据从我创建的元数据表中获取的信息生成的。
Since I don't know how many and what type of fields are present, I am giving dynamic id's to them. I am using Struts 2 tags in my JSP.
因为我不知道有多少和什么类型的字段存在，我给id他们动态的。我在我的 JSP 中使用 Struts 2 标签。
The issue is with the <s:select>tag: when I give scriplet within the idattribute, it displays the following error :
问题出在<s:select>标签上：当我在id属性中提供 scriplet 时，它显示以下错误：
org.apache.jasper.JasperException: /success.jsp(83,12) quote symbol expected
org.apache.jasper.JasperException: /success.jsp(83,12) 需要引号
<s:if test="%{#masterColDO.controlType=='dropdown'}">
<s:select styleClass="login-textbox"
style="width:130px"
list="#masterColDO.validation"
name="chngdColumnValues"
id=<%="columnId" + count%> />
</s:if>
<s:else>
<input type=<s:property value="#masterColDO.controlType" />
class="login-textbox "
name="chngdColumnValues"
id=<%="columnId" + count%> />
</s:else>
Javascript is as follows:
Javascript如下：
var addUpdateBtnId = document.getElementById('addUpdateBtnId');
addUpdateBtnId.value='Update';
addUpdateBtnId.onclick = function() {
onClickUpdateBtn(rowIndex);
};
var selectedUpdateRow = xmlhttp.responseText.split(",");
for(var i = 0; i < selectedUpdateRow.length; i++){
var columnElementId = "columnId"+i;
document.getElementById(columnElementId).value = selectedUpdateRow[i];
}
document.getElementById("columnId"+(primaryKeyPos-1)).readOnly = true;
回答by Andrea Ligios
Scriptlets are the old way of doing things, you should avoid writing Javacode in JSP's at all;
Struts2 helps you achieving the same goals using its tags and OGNLonly.
Scriptlets 是旧的做事方式，您应该完全避免Java在JSPs 中编写代码；
Struts2OGNL仅使用其标签帮助您实现相同的目标。
The <input />part is working because you are injecting a scriptletinside an HTML tag, that is allowed.
该<input />部分正在工作，因为您scriptlet在 HTML 标记内部注入了，这是允许的。
The <s:select />part is not working because you are injecting a scriptletinside an Struts2 tag, that is not allowed.
该<s:select />部分无法正常工作，因为您scriptlet在 Struts2 标签内注入了，这是不允许的。
To make it work, you should use #attrsyntax in OGNLto access the Javavariables declared in Scriptletsand pushed by youin the Page Context, like this (completely untested):
为了使它的工作，你应该使用#attr语法OGNL访问的Java变量声明Scriptlets，并推动通过你在Page Context，像这样（没有经过充分测试）：
<%
for (int counter=0;counter<myList.size();counter++) {
// pushing it into the pageContext
pageContext.setAttribute("counter",counter);
%>
<s:select cssClass="login-textbox"
cssStyle="width:130px"
list="#masterColDO.validation"
name="chngdColumnValues"
id="%{'columnId' + #attr['counter']}" />
<%
}
%>
However, even if it's technically possible, it is discouraged. You should use the pure Struts2 way for that, that would be the following:
但是，即使技术上可行，也不鼓励这样做。您应该使用纯 Struts2 方式，如下所示：
<s:iterator value="myList" status="ctr">
<s:select cssClass="login-textbox"
cssStyle="width:130px"
list="#masterColDO.validation"
name="chngdColumnValues"
id="%{'columnId' + #ctr.index}" />
</s:iterator>
P.S: Struts tags doesn't have any styleClassattribute; you can use cssClassand/or cssStyle;
And, if controlTypeis a String, you should use .equalsinstead of ==: <s:if test="%{#masterColDO.controlType.equals('dropdown')}">.
PS：Struts标签没有任何styleClass属性；您可以使用cssClass和/或cssStyle；
而且，如果controlType是一个字符串，你应该使用.equals，而不是==：<s:if test="%{#masterColDO.controlType.equals('dropdown')}">。
回答by Lukasz Lenart
You should rather use Struts2 expression syntax likes this:
你应该使用像这样的 Struts2 表达式语法：
id="%{'columnId' + count}"
回答by arvin_codeHunk
Struts2 usage valuestacks, So this count should be fetched in ognl manner, try something like this:
Struts2 使用 valuestacks，所以这个计数应该以 ognl 方式获取，尝试这样的事情：
id="%{'columnId'+count}"
