Java 如何在 JSON 对象中获取 JSON 数组？
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How to Get JSON Array Within JSON Object?
提问by Tash Nar
This is my JSON:
这是我的 JSON：
{
"data": [
{
"id": 1,
"Name": "Choc Cake",
"Image": "1.jpg",
"Category": "Meal",
"Method": "",
"Ingredients": [
{
"name": "1 Cup Ice"
},
{
"name": "1 Bag Beans"
}
]
},
{
"id": 2,
"Name": "Ice Cake",
"Image": "dfdsfdsfsdfdfdsf.jpg",
"Category": "Meal",
"Method": "",
"Ingredients": [
{
"name": "1 Cup Ice"
}
]
}
]
}
And this is how I am getting the id and name, you can see this part works fine in returning JSON values that are not array values.
这就是我获取 id 和 name 的方式，您可以看到这部分在返回非数组值的 JSON 值时工作正常。
//getting whole json string
JSONObject jsonObj = new JSONObject(jsonStr);
//extracting data array from json string
JSONArray ja_data = jsonObj.getJSONArray("data");
int length = jsonObj .length();
//loop to get all json objects from data json array
for(int i=0; i<length; i++)
{
JSONObject jObj = ja_data.getJSONObject(i);
Toast.makeText(this, jObj.getString("Name"), Toast.LENGTH_LONG).show();
// getting inner array Ingredients
JSONArray ja = jObj.getJSONArray("Ingredients");
int len = ja.length();
}
Now i'm trying to get the values from the ingredients array and I am not sure how to get them? This is what I have been trying thus far.
现在我试图从成分数组中获取值，但我不知道如何获取它们？这是我迄今为止一直在尝试的。
//getting whole json string
JSONObject jsonObj = new JSONObject(jsonStr);
//extracting data array from json string
JSONArray ja_data = jsonObj.getJSONArray("data");
int length = jsonObj .length();
//loop to get all json objects from data json array
for(int i=0; i<length; i++)
{
JSONObject jObj = ja_data.getJSONObject(i);
Toast.makeText(this, jObj.getString("Name"), Toast.LENGTH_LONG).show();
// getting inner array Ingredients
JSONArray ja = jObj.getJSONArray("Ingredients");
int len = ja.length();
// getting json objects from Ingredients json array
for(int j=0; j<len; j++)
{
JSONObject json = ja.getJSONObject(j);
Toast.makeText(this, json.getString("name"), Toast.LENGTH_LONG).show();
}
}
But doing it this way is not working, how can I get it to work?
但是这样做是行不通的，我怎样才能让它工作？
回答by Ronak Joshi
Solved, use array list of string to get name from Ingredients. Use below code:
解决了，使用字符串数组列表从成分中获取名称。使用以下代码：
JSONObject jsonObj = new JSONObject(jsonStr);
//extracting data array from json string
JSONArray ja_data = jsonObj.getJSONArray("data");
int length = ja_data.length();
//loop to get all json objects from data json array
for(int i=0; i<length; i++){
JSONObject jObj = ja_data.getJSONObject(i);
Toast.makeText(this, jObj.getString("Name"), Toast.LENGTH_LONG).show();
// getting inner array Ingredients
JSONArray ja = jObj.getJSONArray("Ingredients");
int len = ja.length();
ArrayList<String> Ingredients_names = new ArrayList<>();
for(int j=0; j<len; j++){
JSONObject json = ja.getJSONObject(j);
Ingredients_names.add(json.getString("name"));
}
}
回答by Shadow
JSONObject jsonObject =new JSONObject(jsonStr);
JSONArray jsonArray = jsonObject.getJSONArray("data");
for(int i=0;i<jsonArray.length;i++){
JSONObject json = jsonArray.getJSONObject(i);
String id = json.getString("id");
String name=json.getString("name");
JSONArray ingArray = json.getJSONArray("Ingredients") // here you are going to get ingredients
for(int j=0;j<ingArray.length;j++){
JSONObject ingredObject= ingArray.getJSONObject(j);
String ingName = ingredObject.getString("name");//so you are going to get ingredient name
Log.e("name",ingName); // you will get
}
}
回答by Shadow
I guess this will help you.
我想这会帮助你。
JSONObject jsonObj = new JSONObject(jsonStr);
JSONArray ja_data = jsonObj.getJSONArray("data");
int length = jsonObj.length();
for(int i=0; i<length; i++) {
JSONObject jsonObj = ja_data.getJSONObject(i);
Toast.makeText(this, jsonObj.getString("Name"), Toast.LENGTH_LONG).show();
// getting inner array Ingredients
JSONArray ja = jsonObj.getJSONArray("Ingredients");
int len = ja.length();
ArrayList<String> Ingredients_names = new ArrayList<>();
for(int j=0; j<len; j++) {
JSONObject json = ja.getJSONObject(j);
Ingredients_names.add(json.getString("name"));
}
}
回答by Abhishek Jaiswal
JSONObject jsonObj = new JSONObject(jsonString);
JSONArray jArray = jsonObj.getJSONArray("data");
int length = jArray.length();
for(int i=0; i<length; i++)
{
JSONObject jObj = jArray.getJSONObject(i);
String id = jObj.optString("id");
String name=jObj.optString("name");
JSONArray ingredientArray = jObj.getJSONArray("Ingredients");
int size = ingredientArray.length();
ArrayList<String> Ingredients = new ArrayList<>();
for(int j=0; j<size; j++)
{
JSONObject json = ja.getJSONObject(j);
Ingredients.add(json.optString("name"));
}
}
回答by Iúri Batista Teles
Your int length = jsonObj.length();should be int length = ja_data.length();
你int length = jsonObj.length();应该是int length = ja_data.length();
回答by Amar
Gson gson = new Gson();
Type listType = new TypeToken<List<Data>>() {}.getType();
List<Data> cartProductList = gson.fromJson(response.body().get("data"), listType);
Toast.makeText(getContext(), ""+cartProductList.get(0).getCity(), Toast.LENGTH_SHORT).show();
