java Spring MVC - 从表单的 JSP 列表中访问对象
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Spring MVC - accessing objects from a list in JSP for a form
提问by Edgar.A
I am trying to create a form with multiple objects being passed.
I am trying to create a form where you can find 'product' and 'customer' and add them to order.
I have 2 model classes Customerand Product. Customerhas phoneNovariable, Producthas namevariable.
I found that easiest way to pass multiple objects is to add them to list and pass Listto a View. That's what I'm doing, but accessing those model objects is a different story.
我正在尝试创建一个传递多个对象的表单。我正在尝试创建一个表单，您可以在其中找到“ product”和“ customer”并将它们添加到订单中。我有 2 个模型类Customer和Product. Customer有phoneNo变，Product有name变。我发现传递多个对象的最简单方法是将它们添加到列表并传递List给View. 这就是我正在做的事情，但访问这些模型对象是另一回事。
Controller class:
控制器类：
@Controller
public class OrderController {
@RequestMapping(value="/create_order", method= RequestMethod.GET)
public ModelAndView create_order() {
Map<String, Object> model = new HashMap<String, Object>();
model.put("customer", new Customer());
model.put("product", new Product());
return new ModelAndView("create_order", "command", model);
}
}
Page:
页：
<form:form method="POST" action="/Persistence_Web/order_confirmation" commandName="model">
<table>
<!-- I tried few different ways of writing it and all fail -->
<tr><form:label path="model[0].phoneNo">Customer phone number</form:label></tr>
<tr><form:input path="model[0].phoneNo"></form:input></tr>
....
采纳答案by Jordi Castilla
To refer the attributes Product.nameand Customer.phoneNoin your model, you have to refer the names you give in the model plus the attribute name (that must have a getter in the class!!!)
要引用的属性Product.name，并Customer.phoneNo在模型中，你必须参考你在型号后加属性名称给出的名称（必须在类中有一个getter！ ）
<tr><form:input path="${customer.phoneNo}"></form:input></tr>
<tr><form:input path="${product.name}"></form:input></tr>
*The attributes in the classes MUST have getters and setters if you want to manipulate them in the view. The naming must be:
*如果你想在视图中操作它们，类中的属性必须有 getter 和 setter。命名必须是：
private int attributeName
public int getAttributeName()
BUT: as long as the getter method in the class is like your variable namein the view. You can have a getMyCalculation()method WITHOUTmyCalculationattribute in order to calculate totals, averages, formatting dates, or whatever you need to show in the view but not store in the model.
但是：只要类中的 getter 方法就像您在视图中的变量名。您可以使用WITHOUT属性的getMyCalculation()方法来计算总计、平均值、格式化日期或您需要在视图中显示但不存储在模型中的任何内容。myCalculation
Also, for various Productsor Customersuse a list:
此外，对于各种Products或Customers使用列表：
List<Customer> customers = // fill the list!!!
model.put("customers", customers);
And iterate with a <for:earch>
并用一个迭代 <for:earch>
<c:forEach items="${customers}" var="customer">
<c:out value="${customer.phoneNo}"/>
</c:forEach>
回答by androberz
As far as I understood your question you can't access model object in this way. Please try using spring placeholders ${command.get('customer').phoneNo}.
据我了解您的问题，您无法以这种方式访问模型对象。请尝试使用 spring 占位符${command.get('customer').phoneNo}。
