String class

indexOf()

Locates a character or String within another String. By default, searches from the beginning of the String, but can also start from a given index, allowing for the locating of all instances of the character or String.

// SYNTAX
string.indexOf(val)
string.indexOf(val, from)

// PROTOTYPES
int indexOf( char ch ) const;
int indexOf( char ch, unsigned int fromIndex ) const;
int indexOf( const String &str ) const;
int indexOf( const String &str, unsigned int fromIndex ) const;

Parameters:

  • string: a variable of type String
  • val: the value to search for - char or String
  • from: the index to start the search from

Returns: The index of val within the String, or -1 if not found. The index value is 0-based.