Struts 2中支持地图的Actionform替代方案 [英] Map-backed Actionform alternative in Struts 2

问题描述

在Struts 1中，我使用了由地图支持的操作表单获取动态字段值.

In Struts 1, I have used map-backed action form to get dynamic fields values.

public MyForm extends ActionForm {
    private final Map values = new HashMap();
    public void setValue(String key, Object value) {
       values.put(key, value);
    }
    public Object getValue(String key) {
      return values.get(key);
    }
}

下面是我使用的代码.

JSP

<form action="/SaveAction.do">
<input type="text" name="value(dynamicNames)" value="some value">
</form>

操作

public class SaveAction extends ActionSupport implements ModelDriven<MyForm> {
    private MyForm myForm = new MyForm(); 
    @Override
    public MyForm getModel() {
            return myForm;
    }
    public void setMyForm(MyForm myForm){
            this.myForm = myForm;
    }
    public MyForm getMyForm(){
            return myForm;
    }
    public String execute(){
            MyForm formData = getMyForm();//Here I am getting empty object.
            return "SUCCESS";
    }
}

表格

public MyForm {
    private final Map values = new HashMap();
    public void setValue(String key, Object value) {
       values.put(key, value);
    }
    public Object getValue(String key) {
      return values.get(key);
    }
}

如何在Struts 2中实现相同的功能?

How to achieve the same functionality in Struts 2 ?

推荐答案

您应将表单的字段映射到这样的动作

You should map the fields of the form to the action like this

<s:textfield name="myForm.values['%{dynamicNames}']"/> 

尚不清楚dynamicNames的值是什么，实际上它应该是迭代映射时将值推入值堆栈的对象的键，并且在您运行模型驱动时，代码将看起来像

It doesn't clear what value is for dynamicNames, actually it should be the key for the object pushed on the value stack while iterating the map and as soon as you running model driven the code will look like

<s:iterator value="values">
  <s:textfield name="myForm.values['%{key}']"/>
</s:iterator>

OGNL将负责此类名称的映射，并在您提交表单时在表单和操作中填充字段的值.

OGNL will take care of the mapping such names and populate values of the fileds in the form and in the action when you submit the form.

此外，如果需要将用户输入的值放置到另一个对象(例如myForm2)，则可以使用文本字段的值属性value="%{value}"从第一个模型填充表单.

In addition if you need to place the values entered by user to another object say myForm2 then you could use value attribute value="%{value}" of the textfield to populate the form from the first model.

请参阅参考指南，了解如何使用模型驱动界面和模型驱动的拦截器.另外，还提供了参考资料，以帮助您了解对象如何从按类型转换动作对象.

See the reference guide how to use model driven interface and model driven interceptor. Also there's a reference to get you know how objects from the form converted by type to the action objects.

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