Strings
Method
.toUpperCase()
var s = 'string interpolation';
print('That deserves all caps. ' + '${s.toUpperCase()} is very handy!');
// 'That deserves all caps. STRING INTERPOLATION is very handy!'Lists
A list can be created by List<int> list = [ 1 , 2 , 3 ] ; var list = [ 1 , 2 , 3 ] ; spread operator ( ... ) var list ; var list2 = [ 0 , ...?list] ; if the list is null, need to use null-aware spread operator ( ...? ) var list ; var list2 = [ 0 , ...list] ; print(list2) ; //[ERROR:flutter/lib/ui/ui_dart_state.cc(166)] Unhandled Exception: NoSuchMethodError: The getter 'iterator' was called on null. for-in var collection = [ 1 , 2 , 3 ] ; for ( var x in collection) { print(x) ; // 1 2 3 } Method .length var list = [ 1 , 2 , 3 ] ; print(list. length ) ; //3 .forEach() void printElement(int element) { print(element) ; } var list = [ 1 , 2 , 3 ] ; // Pass printElement as a parameter. list.forEach(printElement) ; .indexOf() var list = [ 'apples' , 'bananas' , 'oranges' ] ; list.forEach((item) { print( ' ${list.indexOf(item)} : $item ' ) ; }) ; // 0: apples // 1: bananas // 2: oranges arrow notation: list.forEach( ...
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