arduino 的 json 测试

源程序

 1 #include <ArduinoJson.h>
 2 String st1,st2,st3;
 3 
 4 const char* cc1;
 5 const char* cc2;
 6 const char* cc3;
 7 int in1,in2,in3,in4;
 8 void setup() {
 9 
10   Serial.begin(115200);
11     
12   DynamicJsonDocument doc(1024);
13  
14   // WARNING: the string in the input  will be duplicated in the JsonDocument.
15   String input = "{\"sensor\":\"gps\",\"time\":1351824120,\"data\":\"10\"}";
16   deserializeJson(doc, input);
17   JsonObject obj = doc.as<JsonObject>();
18 
19   // You can use a String to get an element of a JsonObject
20   // No duplication is done.
21   long time = obj[String("time")];
22   //
23   //st1=doc["sensor"];  //此句编译不通过，可用以下两句代替,String 对象声明时可用json赋初值，之后不可以;或可采用下面第3句的方法
24   String sensor = doc["sensor"];
25   st1=sensor;
26 
27   st2=doc["data"].as<String>();
28   st3=doc["time"].as<String>();
29 
30   cc1=doc["sensor"];
31   cc2=doc["data"];
32   cc3=doc["time"];
33 
34   in1=doc["time"].as<int>();
35   in2=doc["time"];
36   in3=doc["data"].as<int>();
37   in4=doc["data"];
38   Serial.println();
39   Serial.print("st1:");  Serial.println(st1); 
40   Serial.print("st2:");  Serial.println(st2); 
41   Serial.print("st3:");  Serial.println(st3); 
42   Serial.print("cc1:");  Serial.println(cc1); 
43   Serial.print("cc2:");  Serial.println(cc2); 
44   Serial.print("cc3:");  Serial.println(cc3); 
45   Serial.print("in1:");  Serial.println(in1,10); 
46   Serial.print("in2:");  Serial.println(in2,10); 
47   Serial.print("in3:");  Serial.println(in3,10); 
48   Serial.print("in4:");  Serial.println(in4,10); 
49   
50   double latitude = doc["data"][0];
51   double longitude = doc["data"][1];
52 
53   // Print values.
54   Serial.println(sensor);
55   Serial.println(time);
56   Serial.println(latitude, 6);
57   Serial.println(longitude, 6);
58 
59   obj["sensor"] = "new gps";
60   obj["code"] = 200;
61   // Lastly, you can print the resulting JSON to a String
62   String output;
63   serializeJson(doc, output);
64 
65   Serial.println(output);
66 }
67 
68 void loop() {
69   // not used in this example
70 }

View Code

串口输出：

16:47:40.786 -> st1:gps
16:47:40.786 -> st2:10
16:47:40.786 -> st3:1351824120
16:47:40.786 -> cc1:gps
16:47:40.786 -> cc2:10
16:47:40.786 -> cc3:
16:47:40.786 -> in1:1351824120
16:47:40.786 -> in2:1351824120
16:47:40.786 -> in3:10
16:47:40.786 -> in4:10
16:47:40.786 -> gps
16:47:40.786 -> 1351824120
16:47:40.786 -> 0.000000
16:47:40.786 -> 0.000000
16:47:40.786 -> {"sensor":"new gps","time":1351824120,"data":"10","code":200}