从arduino获取数据并通过ethienet存储在数据库中

I am getting data from arduino and stored in database through ethienet. But when i got value ambientemp from arduino. it showed correct value when i tested on serial monitor. but when I use sprintf() I got -3275 or 0 value, which it is not correct value. Here is my partial code in sketch, please help...Here is guy doing his project. The result on Sketch serial montior is: ambientTemp 23.55 and then GET /getData/temp.php?t=-3278 I copied some of him: getting data and stored it into mysql

void getData() {
  double ambientTemp=23.55; //to make it easy I assign ambientTemp a value.
unsigned long previousMillis = 0;
unsigned long currentMillis = 0;
long interval = 10000; 
  char strURL[70];


   EthernetClient client;
  // If there's a successful connection, send the HTTP POST request
   currentMillis = millis();
  if(currentMillis - previousMillis > interval) {
    previousMillis = currentMillis;

  if (client.connect(server, 80)) {
    Serial.println("get data connecting...");

    //client.println("GET /getData/temp.php?t=%d,temp HTTP/1.1");
   // delay(10000);
     Serial.println("ambientTemp");
  Serial.println(ambientTemp);
    sprintf(strURL,"GET /getData/temp.php?t=%d",ambientTemp);
    delay(50000);

    client.print(strURL);
    client.println();
   // client.print(strURL);
    Serial.print(strURL);



  } 
  else {
    // If you couldn't make a connection:
    Serial.println("Connection failed");
    Serial.println("Disconnecting.");
    client.stop();
  }
}
}

推荐答案

您需要阅读 C 格式规范.%d" 表示采用相应的变量(在您的情况下为 ambientTemp)并将其解释为整数.所以运行时代码正在做的是查看组成双精度的字节，并解释其中的前 2 个整数.不是你想要的......使用％f"作为格式说明符......