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This example is for Wiring version 1.0 build 0100+. If you have a previous version, use the examples included with your software. If you see any errors or have comments, please let us know.

String startWith() and endsWith() by Tom Igoe
Examples of how to use startsWith() and endsWith() in a String

    void setup()
    {
      Serial.begin(9600);
      Serial.println("\n\nString startsWith() and endsWith():");
    }

    void loop()
    {
      // startsWith() checks to see if a String starts with a particular substring:
      String stringOne = "HTTP/1.1 200 OK";
      Serial.println(stringOne);
      if (stringOne.startsWith("HTTP/1.1"))
      {
        Serial.println("Server's using http version 1.1");
      }

      // you can also look for startsWith() at an offset position in the string:
      stringOne = "HTTP/1.1 200 OK";
      if (stringOne.startsWith("200 OK", 9))
      {
        Serial.println("Got an OK from the server");
      }

      // endsWith() checks to see if a String ends with a particular character:
      String sensorReading = "sensor = ";
      sensorReading += analogRead(A0);
      Serial.print(sensorReading);
      if (sensorReading.endsWith(0))
      {
        Serial.println(". This reading is divisible by ten");
      }
      else
      {
        Serial.println(". This reading is not divisible by ten");
      }

      // do nothing while true:
      while (true);
    }