java 如何检测在单个 Action 类中的多个提交按钮场景中单击的提交按钮？
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How to detect submit button clicked in multiple submit buttons scenario in single Action class?
提问by null
I have a form in a jsp. There are two submit buttons: "Search" and "Add New" button.
我在jsp中有一个表单。有两个提交按钮：“搜索”和“添加新”按钮。
<s:form name="searchForm" action="employeeAction" method="post">
<s:textfield name="id" label="Employee ID"/>
<s:textfield name="name" label="Employee Name"/>
<s:submit value="Search"/>
<s:submit value="Add New"/>
</s:form>
In struts.xml
在 struts.xml
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC
"-//Apache Software Foundation//DTD Struts Configuration 2.3//EN"
"http://struts.apache.org/dtds/struts-2.3.dtd">
<struts>
<constant name="struts.enable.DynamicMethodInvocation" value="false" />
<constant name="struts.devMode" value="true" />
<package name="default" namespace="/" extends="struts-default">
<default-action-ref name="index" />
<global-results>
<result name="error">/error.jsp</result>
</global-results>
<global-exception-mappings>
<exception-mapping exception="java.lang.Exception" result="error"/>
</global-exception-mappings>
</package>
<package name="example" namespace="/example" extends="default">
<action name="employeeAction" class="example.EmployeeAction">
<result name="search">/example/search.jsp</result>
<result name="add" type="redirect">/example/add.jsp</result>
</action>
</package>
</struts>
In Struts Action class, we know that there is only one method that processing http request, that is execute()method.
在Struts Action类中，我们知道处理http请求的方法只有一种，就是execute()方法。
In my expected case, when I clicked Searchbutton, it will perform searching data and render data to /example/search.jsp, when I clicked Add Newbutton, it will perform redirecting page to /example/add.jsp. However, both buttons when clicked will go into execute() method. So I need to know how to detect which button clicked in the execute()method.
在我预期的情况下，当我单击“搜索”按钮时，它将执行搜索数据并将数据呈现到/example/search.jsp，当我单击“添加新”按钮时，它将执行重定向页面到/example/add.jsp。但是，两个按钮在被点击时都会进入 execute() 方法。所以我需要知道如何检测execute()方法中点击了哪个按钮。
The scenario looks like this
场景是这样的
public class EmployeeAction extends ActionSupport {
public String execute() throws Exception {
//PSEUDOCODE
//IF (submitButton is searchButton)
// return doSearch();
//ELSE IF (submitButton is addNewButton)
// return doAddNew();
return SUCCESS;
}
public String doSearch() throws Exception {
//perform search logic here
return "search";
}
public String doAddNew() throws Exception {
return "add";
}
}
回答by Aleksandr M
You can define two actions in struts.xmlfile and use actionattribute of <s:submit>tag in order to submit to different actions http://struts.apache.org/docs/submit.html.
您可以在struts.xml文件中定义两个动作并使用标签的action属性，<s:submit>以便提交到不同的动作http://struts.apache.org/docs/submit.html。
In JSP:
在 JSP 中：
<s:submit value="Search" action="searchEmployeeAction"/>
<s:submit value="Add New" action="addEmployeeAction"/>
In struts.xml:
在 struts.xml 中：
<action name="addEmployeeAction" method="add" class="example.EmployeeAction">
<result>/example/add.jsp</result>
</action>
<action name="searchEmployeeAction" method="search" class="example.EmployeeAction">
<result>/example/search.jsp</result>
</action>
And in your action create two public Stringmethods addand search.
并在您的操作中创建两个public String方法add和search.
Read about Multiple Submit Buttons http://struts.apache.org/docs/multiple-submit-buttons.html.
阅读多个提交按钮http://struts.apache.org/docs/multiple-submit-buttons.html。
Update
更新
Starting from Struts2 version 2.3.15.3 you need to set struts.mapper.action.prefix.enabledconstant to true in order to enable support for action:prefix.
从 Struts2 版本 2.3.15.3 开始，您需要将struts.mapper.action.prefix.enabled常量设置为 true 以启用对action:前缀的支持。
Put that in your struts.xmlfile:
把它放在你的struts.xml文件中：
<constant name="struts.mapper.action.prefix.enabled" value="true" />
回答by Sumit Desai
In your model layer, define a Stringproperty named 'button'. Now, for both your submit buttons, specify nameor propertyattribute as 'button'. So, in your execute()method, in property 'button', you will get the corresponding value.
在您的模型层中，定义一个String名为“button”的属性。现在，对于您的提交按钮，指定name或property属性为“按钮”。因此，在您的execute()方法中，在属性“button”中，您将获得相应的值。
