How to read a string value with a delimiter on Arduino?

I have to manage servos from a computer.

So I have to send manage messages from computer to Arduino. I need manage the number of servo and the corner. I'm thinking of sendin something like this : "1;130" (first servo and corner 130, delimeter ";").

Are there any better methods to accomplish this?

Here is my this code :

String foo = "";
void setup(){
   Serial.begin(9600);
}

void loop(){
   readSignalFromComp();
}

void readSignalFromComp() {
  if (Serial.available() > 0)
      foo = '';
  while (Serial.available() > 0){
     foo += Serial.read(); 
  }
  if (!foo.equals(""))
    Serial.print(foo);
}

This doesn't work. What's the problem?