如何從JavaScript中的另一個字典的鍵更改字典的鍵？

Question

我有一本字典dict1:{Name:"Alex", 3: "61"}。我創建了一個包含相同鍵值對的副本字典dict2。然後我將dict2作爲參數發送給一個函數，然後轉換爲這些值：dict2={1: "Alex",undefined: "61"}。

有人可以幫我編寫代碼來代替undefined:61到原始字典中的代碼嗎？最終的字典必須是：dict={1: "Alex",3: "61"};

dict1={Name:"Alex", 3: "61"}; 
dict2={Name:"Alex", 3: "61"}; //created a copy of original dictionary 
function(dict2){ 
    //some function that converts dict2 to the following value. 
} 
console.log(dict2); //dict2={1: "Alex",undefined: "61"} 

//now i want to write the code to substitute the undefined key-value pair to the one present in the original. 
//my final dict has to be as follows: 
dict={1: "Alex",3: "61"}; 

Answer 1

獲取和存儲的財產"undefined"值，delete"undefined"財產;迭代屬性，值爲dict1，如果屬性值與存儲值匹配，則將屬性設置爲dict2，將屬性名稱匹配爲dict1將存儲變量設置爲set屬性的值。

dict1 = { 
 
    Name: "Alex", 
 
    3: "61" 
 
}; 
 

 
dict2 = { 
 
    1: "Alex", 
 
    undefined: "61" 
 
}; 
 

 
let {undefined:val} = dict2; 
 

 
delete dict2["undefined"]; 
 

 
for (let [key, prop] of Object.entries(dict1)) { 
 
    if (prop === val) dict2[key] = val; 
 
} 
 

 
console.log(dict2);

Answer 2

你可以這樣做：

1. 遍歷第一目標（dict1），並創建一個新的對象，可以說temp其中鍵和值是顛倒的。所以臨時看起來像{Alex：Name，61：3}。
2. 迭代dict2並在「未定義」鍵處獲取值（本例中爲61），然後從反轉對象中讀取值以獲得3.使用此鍵作爲鍵（3）並放置值（61）。
3. 從dict2中刪除「undefined」鍵。

var dict1 = { 
 
    Name: "Alex", 
 
    3: "61" 
 
}; 
 
var dict2 = { 
 
    1: "Alex", 
 
    undefined: "61" 
 
}; 
 
var temp = {}; 
 
for (var i in dict1) { 
 
    temp[dict1[i]] = i; 
 
} 
 

 
for (var key in dict2) { 
 
    if (key == "undefined") { 
 
    var val = dict2[key]; 
 
    dict2[temp[val]] = val; 
 
    } 
 
} 
 
delete dict2["undefined"]; 
 
console.log(dict2);