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indexOf method

int indexOf (Object element, [ int start = 0 ])

Returns 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.

List<String> notes = ['do', 're', 'mi', 're'];
notes.indexOf('re');    // 1
notes.indexOf('re', 2); // 3

Returns -1 if element is not found.

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;
}

© 2012 the Dart project authors
Licensed under the Creative Commons Attribution-ShareAlike License v4.0.
https://api.dartlang.org/stable/2.0.0/dart-collection/ListMixin/indexOf.html