Serial.find() trouble

[battersn]

Hi, I need to find a symbol in the serial port sent to the hardware, and then execute a command to send an SMS to a specific number, but unfortunately this only works in the first case. Does anyone know what the problem is? Code:

if (Serial.available()>0) {
if (Serial.findUntil(target1,"\0")){
buff = Serial.readString();
sendSMS("number1",buff);
Serial.println(buff);
}
else if (Serial.findUntil("002","\0")){
buff = Serial.readString();
sendSMS("number2",buff);
Serial.println(buff);
}
else if (Serial.findUntil("003","\0")){
buff = Serial.readString();
sendSMS("number3",buff);
Serial.println(buff);
}
}

[wildbill]

Finduntil consumes characters from the serial port. If you have sent 002, those characters were read and discarded looking for target1.

You need to read the data into a buffer and then check which one you got.

[battersn]

Thank you for your explanation. I'm still a beginner and I don't really understand it.Can you tell me what search functions are available in the buffer? Just when I tried to use stream.find arduino ide didn't like it.

[wildbill]

Try readBytesUntil

[aarg]

It's impractical to search in the serial input buffer. You have to read the incoming serial data into a buffer that you have declared in your program. Then you can use strcmp() or strncmp() to find the sequences you are looking for, in that buffer.

[aarg]

@battersn

"003","\0"

This is double terminated. A string constant "003" already has a terminating null embedded.

[battersn]

Thank you, but the string.startsWith function helped me

[aarg]

Great!

[battersn]

Thanks

[aarg]

It's helpful if you post your solution, so other people can benefit from it if they have the same problem.

[battersn]

Solving the problem:If, as in my case, it is necessary to find a certain character at the beginning of the transmitted data in order to execute a certain program, then instead of using the Serial function.find should use the string.startsWith function after writing the data from the port to the buffer with the Serial.ReadString function.