java 将 HashMap 的 ArrayList 转换为 JSON String
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时间：2020-11-03 00:49:32 来源:igfitidea点击:
Convert ArrayList of HashMap into JSON String
提问by Infinity
I want to convert ArrayList<Hashmap<String,String>>to JSONArray. I used
我想转换ArrayList<Hashmap<String,String>>为JSONArray. 我用了
JSONArray array = new JSONArray(array_list);
but it does not work properly it returns
但它不能正常工作它返回
["{image=2130837526, category=Chairs, Quantity=1, price=400, name=chair, prodId=34}","{image=2130837566, category=Mirrors, Quantity=1, price=3000, name=La Fonda, prodId=35}"]
Instead it should return
相反，它应该返回
cartitems=[{"name":"Chair","price":"1001","prodId":"2","category":"Chairs","image":"2130837519","Quantity":"1"},{"name":"Baxton Studio Club Chair","price":"4545","prodId":"5","category":"Chairs","image":"2130837521","Quantity":"1"}]
回答by André Bonna
There are many ways to achieve that. I will explain two ways:
有很多方法可以实现这一目标。我将解释两种方式：
You can do like this:
你可以这样做：
ArrayList<HashMap<String, String>> dataMap = new ArrayList<HashMap<String, String>>();
HashMap<String, String> data1 = new HashMap<String, String>();
data1.put("image", "2130837526");
data1.put("category", "Chairs");
data1.put("Quantity", "1");
HashMap<String, String> data2 = new HashMap<String, String>();
data2.put("image", "2130837566");
data2.put("category", "Mirrors");
data2.put("Quantity", "2");
dataMap.add(data1);
dataMap.add(data2);
List<JSONObject> jsonObj = new ArrayList<JSONObject>();
for(HashMap<String, String> data : dataMap) {
JSONObject obj = new JSONObject(data);
jsonObj.add(obj);
}
JSONArray test = new JSONArray(jsonObj);
System.out.println(test.toString());
Or you can use Hymanson Object Mapper:
或者您可以使用 Hymanson 对象映射器：
Add external libraries to Eclipse Project
将外部库添加到 Eclipse 项目
Java Code
Java代码
ArrayList<HashMap<String, String>> dataMap = new ArrayList<HashMap<String, String>>();
HashMap<String, String> data1 = new HashMap<String, String>();
data1.put("image", "2130837526");
data1.put("category", "Chairs");
data1.put("Quantity", "1");
HashMap<String, String> data2 = new HashMap<String, String>();
data2.put("image", "2130837566");
data2.put("category", "Mirrors");
data2.put("Quantity", "2");
dataMap.add(data1);
dataMap.add(data2);
ObjectMapper objectMapper = new ObjectMapper();
String json = objectMapper.writeValueAsString(dataMap);
System.out.println(json);
Both options will print:
这两个选项都将打印：
[{"image":"2130837526","category":"Chairs","Quantity":"1"},{"image":"2130837566","category":"Mirrors","Quantity":"2"}]
