JSON添加到JSONArray问题 [英] JSON add to JSONArray issue

问题描述

我不是Json最好的.我试图通过循环将一些json对象添加到json数组中，但是问题是每次涉及到循环时，它也会通过新数据来遍历数组中的先前数据.这是我的代码:

Hi All I am not the best at Json. I was trying to add some json object into a json array through a loop, but the problem is everytime it comes to the loop, it also over rides the previous data in the array by the new data. here is my code:

JSONObject jsonObj = new JSONObject();
JSONArray jsonArray = new JSONArray();
if(X.size() > 0)
{
  for (int j = 0; j < X.size(); j++)
   {
    zBean aBean = (zBean)X.get(j);
    jsonObj.put(ID,newInteger(aBean.getId()));
    jsonObj.put(NAME,aBean.getName());
    jsonArray.add(jsonObj);
   }
}

给出X.size = 2的示例:

example given X.size = 2:

when j=0
jsonObj => {"Name":"name1","Id":1000}
jsonArray => [{"Name":"name1","Id":1000}]

when j = 1
jsonObj => {"Name":"name2","Id":1001}
jsonArray => [{"Name":"name2","Id":1001},{"Name":"name2","Id":1001}]

我希望我的例子足够清楚.

I hope my example is clear enough.

如果有人可以在这里帮助我，我将不胜感激.

Id be grateful if anyone can help me here.

推荐答案

您需要在循环的每次迭代中创建一个新的jsonObj引用:

You need to create a new jsonObj reference with every iteration of the loop:

for (int j = 0; j < X.size(); j++)
 {
  zBean aBean = (zBean)X.get(j);
  jsonObj = new JSONObject();
//^^^^^^^^^^^^^^^^^^^^^^^^^^^ add this line
  jsonObj.put(ID,newInteger(aBean.getId()));
  jsonObj.put(NAME,aBean.getName());
  jsonArray.add(jsonObj);
 }

否则，您将一遍又一遍地更新同一实例，并将对同一对象的引用多次添加到数组中.由于它们都是相同的引用，因此对其中一个的更改会影响数组中的所有它们.

Otherwise you are updating the same instance over and over again, and adding a reference to the same object many times to the array. Since they are all the same reference, a change to one of them affects all of them in the array.

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