将数据库获取的数据转为json ，再加入JSONArray中，用   jsonArray.put(json);

//获取数据库的信息,转为json格式

JSONArray jsonArray = new JSONArray();
		String jsons = "";
		JSONObject json = new JSONObject();
		List<CarImageUser> CarImageUsers = new ArrayList<CarImageUser>();
		CarImageUser c = new CarImageUser();
		InterCarSomething ic = new CarSomething();
		List<Carinfo> cif = ic.GetCatInfo();
		List<CarImageUser> users = ic.User();
		for(int i=0;i<cif.size();i++){
			c.setLocationQ(users.get(i).getLocationQ());
			c.setLocationZ(users.get(i).getLocationZ());
			c.setUserName(users.get(i).getUserName());
			c.setDate(users.get(i).getDate());
			c.setTime(users.get(i).getTime());
			c.setCarNoYes(users.get(i).isCarNoYes());
			c.setCityNoYes(users.get(i).isCityNoYes());
			c.setImageViewName(users.get(i).getImageViewName());
			c.setImageViewPath(users.get(i).getImageViewPath());
			CarImageUsers.add(c);
			json = new JSONObject(c);
			jsonArray.put(json);
		}

//将String写入文件中try 

try {
					String jsonString = jsonArray.toString();
					System.out.print(FileName);
					File filejson = new File(Path.Path.FilePath+FileName+".json");
					if(!filejson.exists()){
						filejson.createNewFile();
					}
					FileWriter filewriter = new FileWriter(filejson.getAbsoluteFile());
					BufferedWriter bufferWriter = new BufferedWriter(filewriter);
					bufferWriter.write(jsonString);
					bufferWriter.close();		
			} catch (IOException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
				}