我想將密鑰從“new”更新為“1”。我怎樣才能做到這一點 ？
老一：
Map<String, String> titleTextFieldList = {"new":"title"};
我想要的是：
{"1":"title"}
uj5u.com熱心網友回復：
作為@rosh-dev 狀態。
Map<String, String> titleTextFieldList = {"new":"title"};
Map<String, String> titleTextFieldList2 ={"1": titleTextFieldList['new']}
print('$titleTextFieldList2');
uj5u.com熱心網友回復：
看一看。您可以創建一個新地圖并檢查密鑰是否匹配，然后將其替換為另一個密鑰。
void main() {
Map<String, String> titleTextFieldList = {"new": "title", "test": "test"};
Map<String, String> newMap = {};
titleTextFieldList.forEach((i, value) {
if (i == "new") {
newMap["1"] = value;
} else {
newMap.addAll({"$i": "$value"});
}
});
print(newMap); //{1: title, test: test}
}
uj5u.com熱心網友回復：
void main() {
Map<String, String> titleTextFieldList = {"new": "title","b":"kkk"};
Map<String, String> newMap = {};
int i = 1;
titleTextFieldList.keys.toList().forEach((key) {
newMap.addAll( {"${key=='new'?'1':key}": titleTextFieldList[key]}); i ; });
print(titleTextFieldList);
print(newMap);
}
輸出是：
{"new": "title", "b": "kkk"}
{"1": "title", "b": "kkk"}
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