Question

以下是我的pojo，Action和jsp页面。对于Expense的单个实例，我得到了适当的输入。我想使用ModelDriven从jsp页面获取Expense的多个实例。为此，我创建了多个<div class="Expense">...</div>，但我不知道我应该在Action类中做出哪些更改。如何实现这一点。

Pojo Class

public class Expense  implements java.io.Serializable {
     private Long id;
     private Client client;
     private String param;
     private BigDecimal value;
     private Date dt;
     private Date adddate;
     //getter and setter

}

ActionClass

public class ExpenxeAction extends ActionSupport implements ModelDriven<Expense> {

    Expense e = new Expense();
    ExpenseDAO dao = new ExpenseDAO();
    private LoginCheck lc = null;
    private List<Expense> expenseList = new ArrayList<Expense>();

    public String insertExpense() {
        dao.insert(e);
        return SUCCESS;
    }
   @Override
     public Expense getModel() {
    return e;
  }
}

Jsp页面

 <div class="Expense">
    <label>Expense Type</label>
      <input type="text" name="param"  id="param"/>
     <label>Amount</label>
      <input type="text" name="value" class="form-control" id="value"/>
     <label>Date</label>
     <input type="text" name="dt" class="form-control"  id="dt"/>
   </div>

Answer 1

您应该为expenseList

创建一个getter

public List<Expense> getExpenseList() {
  return expenseList;
}

JSP中的

使用索引属性名称

<s:iterator value="expenseList" status="stat">
   <div class="Expense">
     <label>Expense Type</label>
     <s:textfield name="expenseList[%{#stat.index}].param"  id="param"/>
     <label>Amount</label>
     <s:textfield name="expenseList[%{#stat.index}].value" class="form-control" id="value"/>
     <label>Date</label>
     <s:textfield name="expenseList[%{#stat.index}].dt" class="form-control"  id="dt"/>
   </div>
</s:iterator>

Answer 2

要获取操作类中的Expense对象的数组列表，您需要对代码进行以下更改。

首先，如果您愿意，您必须将ModelDriven<Expense>更改为ModelDriven<List<Expense>>并删除Expense e = new Expense();。所以，最后你的动作类应该是这样的。

public class ExpenxeAction extends ActionSupport implements ModelDriven<List<Expense>>, Preparable {
    ExpenseDAO dao = new ExpenseDAO();
    private LoginCheck lc = null;
    private List<Expense> expenseList = new ArrayList<Expense>();

    public String insertExpense() {
        for (Expense e : expenseList) {     //loop to iterate over each elements
            dao.insert(e);
        }
        return SUCCESS;
    }
    public List<Expense> getExpenseList() {
        return expenseList;
    }

    public void setExpenseList(List<Expense> expenseList) {
        this.expenseList = expenseList;
    }   

   @Override
    public void prepare() throws Exception {
        expenseList = new ArrayList<Expense>(); 
    }

    @Override
    public List<Expense> getModel() {
        return expenseList;
    }
}

现在，您必须更改jsp页面。

<div class="Expense">
    <label>Expense Type</label>
    <input type="text" name="model[0].param"  id="param"/>
    <label>Amount</label>
    <input type="text" name="model[0].value" class="form-control" id="value"/>
    <label>Date</label>
    <input type="text" name="model[0].dt" class="form-control"  id="dt"/>

    <label>Expense Type</label>
    <input type="text" name="model[1].param"  id="param"/>
    <label>Amount</label>
    <input type="text" name="model[1].value" class="form-control" id="value"/>
    <label>Date</label>
    <input type="text" name="model[1].dt" class="form-control"  id="dt"/>

    <label>Expense Type</label>
    <input type="text" name="model[2].param"  id="param"/>
    <label>Amount</label>
    <input type="text" name="model[2].value" class="form-control" id="value"/>
    <label>Date</label>
    <input type="text" name="model[2].dt" class="form-control"  id="dt"/>
</div>

您会注意到我们在jsp代码中提到了

model[index].<pojo_member_variable_name>而不是指定 lstExp[index].<pojo_member_variable_name>

这是因为现在我们希望struts2将值直接设置到这些成员变量中。所以我们提到model[index].<pojo__member_variable_name>，以便struts2自动将值设置到列表中。在上面的代码中，我们创建了3个Expense对象的列表。如果你需要插入更多的值，那么只需增加索引并设置值，剩下的就由struts2为你完成。

如何使用ModelDriven在ArrayList中获取数据

2 个答案: