Question

在jsx中我有一张地图：

var myMap=Map([['rowNumber', '30'], ['id', '80'], ['firstName', '180'], ['lastName', '180'], ['mobile', '180'], ['username', '180'], ['password', '180']])

如何以编程方式添加新元素，例如：[＆＃39; ssn＆＃39;，＆＃39; 12＆＃39;] 到这张地图？

Answer 1

您正在寻找set method：

myMap.set('ssn', '12');

如果你有一个入门元组，你可以使用

const newEntry = ['ssn', '12'];
myMap.set(newEntry[0], newEntry[1]);
// or also
myMap.set(...newEntry) // however that might be confusing

Answer 2

查看地图参考：https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map

您可以使用以下内容向地图添加项目：myMap.set(keyString, "value associated with 'a string'");

Answer 3

您可以使用带扩展语法的set()方法将两个元素的数组添加为键和值。

var myMap = new Map([['rowNumber', '30'], ['id', '80'], ['firstName', '180'], ['lastName', '180'], ['mobile', '180'], ['username', '180'], ['password', '180']])

myMap.set(...['ssn', '12'])
for(var i of myMap) console.log(i)

JavaScript6：将元素（键，值）添加到ES6映射

3 个答案: