Convert List of String to List of int Dart

Question

How to convert a list from one type to another without a for loop?

List <String> lstring = <String>["1", "2"];
List <int> lint = lstring.map(int.parse);

I get the error:

type 'MappedListIterable<String, int>' is not a subtype of type 'List<int>'

hellopeach · Accepted Answer · 2019-03-21 05:55:10Z

34

You need to add a toList() to the end of the second line.

List <String> lstring = <String>["1", "2"];
List <int> lint = lstring.map(int.parse).toList();

This will do it.

answered Mar 21, 2019 at 5:55

hellopeach

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1 Comment

Most Iterable operations are lazy and only executed when the result is actually iterated which toList() needs to do to create a new list.

Solomon Gbadamosi · Accepted Answer · 2021-03-18 10:02:42Z

7

final List<String> lstring = ["1", "2"];
final List<int> newList = lstring.map((e)=>int.parse(e)).toList();

answered Mar 18, 2021 at 10:02

Solomon Gbadamosi

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