How can i avoid String() when converting from int to char?

Projects Programming
1

Reading a bit through the forums i got the message that i should try to avoid String() wherever i can. But i wonder how i could, for instance when i read a value from a sensor that is being returned as a int and want to send that to a webservice (in my case ubidots) that only takes String-Values.
I could convert the int to a char but the only way i found is through conversion to a String.
Is there any other way to circumvent String?

2 
char example[80];
int volts=27;
int temperature=37;
sprintf( example, "volts=%d&temp=%d", volts, temperature );
client.print(example);
3

itoa is another possibility - if you're not using sprintf already, it looks like itoa would use less progmem.

4

wildbill makes a good point. Compiling the code using sprintf() on an Uno generated 3446 bytes of code. Using itoa():

void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
  char example[50] = "volts=";
  char temp[10];
  int volts=27;
  int temperature=37;
  itoa(volts, temp, 10);
  strcat(example, (const char *)temp);
  itoa(temperature, temp, 10);
  strcat(example, "&");
  strcat(example, (const char *)temp);
  Serial.println(example);
}

generated 2222 bytes of code. In most uses, sprintf() is an H-bomb-to-kill-an-ant approach and I usually try to avoid it if I can.

5

It is interesting to look over ways to convert an int to a C string in RAM but consider that getting that int to the webservice, isn't it done through print()?

6

Thank you very much altogether, used both sprintf and itoa, both work great for me!