need help

what si the meaning of : if(command.equals("Relay1On")){ digitalWrite(Relay1, LOW); Serial.println("ON");

kresnamurti:
what si the meaning of : if(command.equals("Relay1On")){ digitalWrite(Relay1, LOW); Serial.println("ON");

Lord only knows. What are you trying to do? Posting all of your code would help.

what si the meaning of : if(command.equals("Relay1On")){ digitalWrite(Relay1, LOW); Serial.println("ON");

If you formatted that code correctly, you'd see more easily what it is doing:

if(command.equals("Relay1On"))
{
   digitalWrite(Relay1, LOW);
   Serial.println("ON");

command is an instance of a class that has a equals() method (probably String). The method takes an argument, and returns a value of true or false. Presumably, command is a String object that could contain the text "Relay1On", and the method is determining if it, indeed, does.

If it does, that is if equals() returned true, the pin whose number is stored in Relay1 is set to LOW, turning a relay on. A message is sent the serial port saying that.

If the command you got is "Relay1On" then you set the Relay1 pin to LOW and send "ON" to the serial port.
If the command you got was not "RELAY1On", do nothing.

ok thanks sir PaulS