js map(Number) All In One
map() 方法創建一個新數組，其結果是該數組中的每個元素是調用一次提供的函數後的返回值。
let newArray = arr.map(callback(currentValue[, index[, array]]) {
// return element for newArray, after executing something
}[, thisArg]);
arr.map(Constructor)
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/map
demo
["1", "2", "3"].map(parseInt);
// (3) [1, NaN, NaN]
["1", "2", "3"].map(Number);
// (3) [1, 2, 3]
parseInt
Number.parseInt(string,[ radix])
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Number/parseInt
parseInt(string [, radix])
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/parseInt
構造函數， 立即執行
new Number(value)
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Number/Number
Number(value)
refs
©xgqfrms 2012-2020
www.cnblogs.com 發佈文章使用：只允許註冊用戶纔可以訪問！