Data Structure
Networking
RDBMS
Operating System
Java
MS Excel
iOS
HTML
CSS
Android
Python
C Programming
C++
C#
MongoDB
MySQL
Javascript
PHP
Physics
Chemistry
Biology
Mathematics
English
Economics
Psychology
Social Studies
Fashion Studies
Legal Studies
- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who
Get the first occurrence of a substring within a string in Arduino
The indexOf() function within Arduino scans a string from the beginning, and returns the first index of the specified substring within the string. The syntax is −
Syntax
myString.indexOf(substr)
where substr is the substring to search for. It can be of type character or string.
Optionally, you can provide a different starting point to begin the search from, in which case, the syntax is −
Syntax
myString.indexOf(substr, from)
where from is the index from where the search should start. This function returns the index of the first occurrence of the substring within the string, or -1, if no match is found.
Example
void setup() {
// put your setup code here, to run once:
Serial.begin(9600);
Serial.println();
String s1 = "Mississippi";
String substr1 = "is";
String substr2 = "os";
Serial.println(s1.indexOf(substr1));
Serial.println(s1.indexOf(substr2));
Serial.println(s1.indexOf(substr1, 3));
}
void loop() {
// put your main code here, to run repeatedly:
}Output
The Serial Monitor output is shown below −
As you can see, in the first case, the index 1 was printed (counting starts from 0). In the second case, since no match was found, -1 was printed. In the third case, we told Arduino to start searching from index 3. Therefore, the next match was found at index 4, and that was printed.
443 Views
