javascript 带有 Onclick 方法的 JSP 和 JSTL
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JSP and JSTL with the Onclick method
提问by Alex Dowining
I have 2 links. In a session i store some data. I want if a user click in a specific link to look into the session and if the appropriate value contained, to continue. Else an AJAX pop up block will appears.
我有2个链接。在会话中，我存储了一些数据。我希望用户单击特定链接以查看会话，如果包含适当的值，则继续。否则会出现一个 AJAX 弹出块。
JAVASCRRIPT pop up block
JAVASCRIPT 弹出块
function displaymessage(title,message,close)
{
resultReturn= $.confirm({
'title' : title,
'message' : message
'buttons' : {
close/*'Yes'*/ : {
'class' : 'blue',
'caption': close,
'action': function(){}
}
}
});
}
JSP with JSTL tags:
带有 JSTL 标签的 JSP：
<div class="header">
<a href="<c:url value='/home'/>">
<a href="<c:url value='/further'/>">
</div>
<c:if test="${not fn:containsIgnoreCase(data, 'mykey')}">
<a id="get" class="right keepScrollPosition"
onclick="return displaymessage('<spring:message code="access.denied.title"/>'
,'<spring:message code="access.denied.message"/>','<spring:message code="access.denied.close"/>');"
href="#" /></a>
</c:if>
For example, if in the session contained the value 'mykey',then can go into the link home, else a pop up will appears. In case, in the session contained the value 'mypassword' and select the further link can continue, but if select the home link a pop up block will appears. I'm stuck and i need some help on how can i do this.Please help me
例如，如果会话中包含值“mykey”，则可以进入链接主页，否则会出现一个弹出窗口。如果会话中包含值 'mypassword' 并选择进一步的链接可以继续，但如果选择主页链接，则会出现一个弹出块。 我被卡住了，我需要一些关于如何做到这一点的帮助。请帮助我
UPDATE
更新
I'm trying the following script but it doesn't work:
我正在尝试以下脚本，但它不起作用：
<li><a href="<c:url value='/home/'/>"<spring:message code="home_page"/>
onclick="if(<c:if test="${not fn:containsIgnoreCase(data, 'mykey')}">){
return displaymessage('<spring:message code="access.denied.title"/>'
,'<spring:message code="access.denied.message"/>','<spring:message code="access.denied.close"/>')" href="#" ;
}
</a>
</li>
回答by atrain
You can't use client-side JS to check a server-side value held in the session. Instead, you need to use JS to make a GET call to a request mapping which runs servers-side code to check the session. Flow could be as follows:
您不能使用客户端 JS 来检查会话中保存的服务器端值。相反，您需要使用 JS 对运行服务器端代码以检查会话的请求映射进行 GET 调用。流程可能如下：
- User clicks button/image/something on page
- JS fires from click, makes AJAX call (e.g.
$.get) to request mapping/check_session.do - Request mapping checks session for value, returns true or false as JSON
- Client-side JS processes returned JSON, blocks or proceeds based on returned value
- 用户点击页面上的按钮/图像/某物
- JS 从点击触发，进行 AJAX 调用（例如
$.get）以请求映射/check_session.do - 请求映射检查会话的值，以 JSON 形式返回真或假
- 客户端JS处理返回的JSON，根据返回值阻塞或继续
Alternatively, use JSTL to access the session and write the session field's value to a hidden form field on the page, which the client-side JS then reads. Example: http://www.steve-farmer.com/examples/el/ui/ses-attr-name.jsp
或者，使用 JSTL 访问会话并将会话字段的值写入页面上的隐藏表单字段，然后客户端 JS 读取该字段。示例：http: //www.steve-farmer.com/examples/el/ui/ses-attr-name.jsp
