W3cubDocs

/Dart 2

indexWhere method

int indexWhere (bool test(E element), [ int start = 0 ])

Returns the first index in the list that satisfies the provided test.

Searches the list from index start to the end of the list. The first time an object o is encountered so that test(o) is true, the index of o is returned.

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

Returns -1 if element is not found.

notes.indexWhere((note) => note.startsWith('k'));    // -1

Implementation

int indexWhere(bool test(E element), [int start = 0]);

© 2012 the Dart project authors
Licensed under the Creative Commons Attribution-ShareAlike License v4.0.
https://api.dart.dev/stable/2.5.0/dart-core/List/indexWhere.html