indexOf method - ListBase class - dart:collection library (original) (raw)

int indexOf(

1. Object? element, [
2. int start = 0 ])

override

The first index of element in this list.

Searches the list from index start to the end of the list. The first time an object o is encountered so that o == element, the index of o is returned.

final notes = <String>['do', 're', 'mi', 're'];
print(notes.indexOf('re')); // 1

final indexWithStart = notes.indexOf('re', 2); // 3

Returns -1 if element is not found.

final notes = <String>['do', 're', 'mi', 're'];
final index = notes.indexOf('fa'); // -1

Implementation

int indexOf(Object? element, [int start = 0]) {
  if (start < 0) start = 0;
  for (int i = start; i < this.length; i++) {
    if (this[i] == element) return i;
  }
  return -1;
}