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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 Case changes by Tom Igoe
Examples of how to change the case of a string

    void setup()
    {
      Serial.begin(9600);
      Serial.println("\n\nString  case changes:");
    }

    void loop()
    {
      // toUpperCase() changes all letters to upper case:
      String stringOne = "<html><head><body>";
      Serial.println(stringOne);
      stringOne.toUpperCase();
      Serial.println(stringOne);

    // toLowerCase() changes all letters to lower case:
      String stringTwo = "</BODY></HTML>";
      Serial.println(stringTwo);
      stringTwo.toLowerCase();
      Serial.println(stringTwo);

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