JSON
创建JSON数据
try {
//首先创建对象中的一个单个键值对
JSONObject root = new JSONObject();
root.put("cat", "it");
//另一个键值对的值是一个数组，数组里装了3个JSON对象，所以再分别搞3个JSONObject对象存放键值对
JSONObject lan1 = new JSONObject();
lan1.put("id", "1");
lan1.put("ide", "Eclipse");
lan1.put("name","Java");
JSONObject lan2 = new JSONObject();
lan2.put("id", "2");
lan2.put("ide", "XCode");
lan2.put("name","Swift");
JSONObject lan3 = new JSONObject();
lan3.put("id", "2");
lan3.put("ide", "Visual Studio");
lan3.put("name","C#");
//在将这3个对象存入一个数组
JSONArray array = new JSONArray();
array.put(lan1);
array.put(lan2);
array.put(lan3);
//再将数组作为键"languages"的值，构成一个对象
root.put("languages", array);
//本例中只将内容输出出来
System.out.println(root.toString());
} catch (JSONException e) {
e.printStackTrace();
}
读取JSON数据
assets/test.json
{
"languages":[
{"id":1,"ide":"Eclipse","name":"Java"},
{"id":2,"ide":"XCode","name":"Swift"},
{"id":3,"ide":"Visual Studio","name":"C#"},
],
"cat","it"
}
try {
InputStream is = getResources().getAssets().open("test.json");
InputStreamReader isr = new InputStreamReader(is, "UTF-8");
BufferedReader br = new BufferedReader(isr);
//将文本中的数据，都读取到一个StringBuilder当中
String line;
StringBuilder builder = new StringBuilder();
while((line=br.readLine()) != null ){
builder.append(line);
}
br.close();
isr.close();
JSONObject root = new JSONObject(builder.toString());
//根据键，获得键对应的值，由于值是String类型，所以用getString
System.out.println("cat="+root.getString("cat"));
//根据键，获得键对应的数组，由于值是一个数组，所以用getJSONArray
JSONArray array = root.getJSONArray("languages");
//由于要遍历数组，所以创建一个for循环
for(int i=0; i < array. length(); i++){
//由于每一个数组当中的元素，也是一个新的JSON对象
JSONObject lan = array.getJSONObject(i);
System.out.println("-------------------");
System.out.println("id="+lan.getInt("id"));
System.out.println("ide="+lan.getString("name"));
System.out.println("name="+lan.getString("name"));
Log.i("tag","-------");
}
} catch (IOException e) {
e.printStackTrace();
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
