Question

让我解释一下目前的状态，然后我会提到这个问题。

在我的jsp页面中，我通过javascript中$getJSON的{{1}}方法调用Struts 2 Action。

以下是代码：

jQuery

我想在我的Struts Action类中读取通过请求发送的json对象。这是我的Action类：

var a = {"id":"ddsa","firstName":"dasda","lastName":"asaas","email":"dasdds"};
var b = {"id":"ddsa","firstName":"dasda","lastName":"asaas","email":"dasdds"};
var c = {"id":"ddsa","firstName":"dasda","lastName":"asaas","email":"dasdds"};

var users = [a,b,c];

   $.getJSON
      (
        "createUser.action",
        {
            "users":users+""
        },
        function (data){
//          alert(data.status);
            if(data.status == "SUCCESS"){
                location.reload();              
            }else{
                alert("Creating User Failed");
            }   
        }
    );

我得到一个像这样的异常堆栈跟踪：

public class ProcessUser extends ActionSupport implements ServletRequestAware {
private HttpServletRequest request;

@Override
public void setServletRequest(HttpServletRequest servletRequest) {
    // TODO Auto-generated method stub
    this.request = servletRequest;
}

public String execute() {


    String data = request.getParameter("users");

    System.out.println("data is :"+data);


    //data = "{\"users\":"+data+"}";

    System.out.println("data is :"+data);


    //data = "{\n  \"users\": [\n    {\n      \"id\": \"ddsa\",\n      \"firstName\": \"dasda\",\n      \"lastName\": \"asaas\",\n      \"email\": \"dasdds\"\n    },\n    {\n      \"id\": \"ddsa\",\n      \"firstName\": \"dasda\",\n      \"lastName\": \"asaas\",\n      \"email\": \"dasdds\"\n    }\n  ]\n}";

    try {
        JSONObject json = (JSONObject)new JSONParser().parse(data);

        JSONArray jsonArray = (JSONArray)json.get("users");

        JSONObject jsonObject = (JSONObject)jsonArray.get(0);

        System.out.println("id:"+jsonObject.get("firstName"));
        /*
        System.out.println("name=" + json.get("users[id"));
        System.out.println("width=" + json.get("users.firstName"));*/
    } catch (ParseException e1) {
        // TODO Auto-generated catch block
        e1.printStackTrace();
    }
 return SUCCESS;
 }

你能帮我解决这个问题。我怎样才能读出那个json对象。

Answer 1

尝试使用以下代码声明数组

JSONArray jsonArray = (JSONArray) JSONSerializer.toJSON( input );

其中input是JSON字符串

Answer 2

经过多次迭代后，我找到了问题的解决方案。

从JavaScript发送请求时，我必须使用JSON.stringify(data)，即

var a = {"id":"ddsa","firstName":"dasda","lastName":"asaas","email":"dasdds"};
var b = {"id":"ddsa","firstName":"dasda","lastName":"asaas","email":"dasdds"};
var c = {"id":"ddsa","firstName":"dasda","lastName":"asaas","email":"dasdds"};

var users = [a,b,c];

$.getJSON
  (
    "createUser.action",
    {
        "users":JSON.stringify(users)
    },
    function (data){
//          alert(data.status);
        if(data.status == "SUCCESS"){
            location.reload();              
        }else{
            alert("Creating User Failed");
        }   
    }
);

在我使用的struts Action类中，

JSONArray jsonArray = (JSONArray) new JSONParser().parse(data);

然后迭代这个数组并得到JOSNObject来获取所有属性值，即

JOSNObject jsonObject = (JSONObject) jsonArray.get(i);

感谢您的支持。

在Struts Action类中读取JSON对象

2 个答案: