Dart Map(マップ)をコピーするサンプル
環境
Windows 11 pro 64bit
Dart 2.18.4
構文
var copy = {…map}
コピー先の変数に「{…map}」（mapはコピー元）を代入します。
使用例
void main() {
var numbers = {
'one': 11,
'two': 22,
'three': 33,
};
var copy = {...numbers};
copy['four'] = 44;
print(numbers);
print(copy);
}
void main() {
var numbers = {
'one': 11,
'two': 22,
'three': 33,
};
var copy = {...numbers};
copy['four'] = 44;
print(numbers);
print(copy);
}
void main() {
var numbers = {
'one': 11,
'two': 22,
'three': 33,
};
var copy = {...numbers};
copy['four'] = 44;
print(numbers);
print(copy);
}
実行結果
{one: 11, two: 22, three: 33}
{one: 11, two: 22, three: 33, four: 44}