Corretions and refinements to the String examples

build/linux/work/examples/08.Strings/StringCharacters/StringCharacters.ino

@@ -0,0 +1,44 @@
+/*
+  String charAt() and setCharAt()
+ 
+ Examples of how to get and set characters of a String
+ 
+ created 27 July 2010
+ modified 2 Apr 2012
+ by Tom Igoe
+ 
+ http://arduino.cc/en/Tutorial/StringCharacters
+ 
+ This example code is in the public domain.
+ */
+
+void setup() {
+  // Open serial communications and wait for port to open:
+  Serial.begin(9600);
+  // this check is only needed on the Leonardo:
+  while (!Serial) ;
+  ;
+
+  Serial.println("\n\nString  charAt() and setCharAt():");
+}
+
+void loop() {
+  // make a string to report a sensor reading:
+  String reportString = "SensorReading: 456";
+  Serial.println(reportString);
+
+  // the reading's most significant digit is at position 15 in the reportString:
+  char mostSignificantDigit = reportString.charAt(15);
+  Serial.println("Most significant digit of the sensor reading is: " + mostSignificantDigit);
+
+  // add blank space:
+  Serial.println();
+
+  // you can alo set the character of a string. Change the : to a = character
+  reportString.setCharAt(13, '='); 
+  Serial.println(reportString);
+
+  // do nothing while true:
+  while(true);
+}
+