🐡
【Flutter】Listのindexの存在チェック
asMap().containsKey
をつかう
List<int> numbers = [1, 2, 3, 4, 5,];
//Check if index 7 is valid
if (numbers.asMap().containsKey(7)) {
print('Exists');
} else {
print('Doesn\'t exist');
}
//[EDIT] Check if item at index 4 exists and is 5
if (numbers.asMap()[4] == 5) {
print("Index 4 = 5");
} else {
print("Index 4 != 5");
}
Ref
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