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/*
String indexOf() and lastIndexOf() functions
Examples of how to evaluate, look for, and replace characters in a String
created 27 July 2010
modified 2 Apr 2012
by Tom Igoe
http://arduino.cc/en/Tutorial/StringIndexOf
This example code is in the public domain.
*/
void setup() {
// Open serial communications and wait for port to open:
Serial.begin(9600);
while (!Serial) {
; // wait for serial port to connect. Needed for Leonardo only
}
// send an intro:
Serial.println("\n\nString indexOf() and lastIndexOf() functions:");
Serial.println();
}
void loop() {
// indexOf() returns the position (i.e. index) of a particular character
// in a string. For example, if you were parsing HTML tags, you could use it:
String stringOne = "<HTML><HEAD><BODY>";
int firstClosingBracket = stringOne.indexOf('>');
Serial.println("The index of > in the string " + stringOne + " is " + firstClosingBracket);
stringOne = "<HTML><HEAD><BODY>";
int secondOpeningBracket = firstClosingBracket + 1;
int secondClosingBracket = stringOne.indexOf('>', secondOpeningBracket );
Serial.println("The index of the second > in the string " + stringOne + " is " + secondClosingBracket);
// you can also use indexOf() to search for Strings:
stringOne = "<HTML><HEAD><BODY>";
int bodyTag = stringOne.indexOf("<BODY>");
Serial.println("The index of the body tag in the string " + stringOne + " is " + bodyTag);
stringOne = "<UL><LI>item<LI>item<LI>item</UL>";
int firstListItem = stringOne.indexOf("<LI>");
int secondListItem = stringOne.indexOf("item", firstListItem + 1 );
Serial.println("The index of the second list item in the string " + stringOne + " is " + secondClosingBracket);
// lastIndexOf() gives you the last occurrence of a character or string:
int lastOpeningBracket = stringOne.lastIndexOf('<');
Serial.println("The index of the last < in the string " + stringOne + " is " + lastOpeningBracket);
int lastListItem = stringOne.lastIndexOf("<LI>");
Serial.println("The index of the last list item in the string " + stringOne + " is " + lastListItem);
// lastIndexOf() can also search for a string:
stringOne = "<p>Lorem ipsum dolor sit amet</p><p>Ipsem</p><p>Quod</p>";
int lastParagraph = stringOne.lastIndexOf("<p");
int secondLastGraf = stringOne.lastIndexOf("<p", lastParagraph - 1);
Serial.println("The index of the second last paragraph tag " + stringOne + " is " + secondLastGraf);
// do nothing while true:
while(true);
}
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