JavaScript數組添加或更新

Question

JavaScript數組推動問題

我有一個目標：

people: [{name: peter, age: 27, email:'peter@abc.com'}] 

我要推：

people.push({ 
     name: 'John', 
     age: 13, 
     email: 'john@abc.com' 
}); 
people.push({ 
     name: 'peter', 
     age: 36, 
     email: 'peter@abc.com' 
}); 

的最後我想要的是：

people: [ 
{name: 'peter', age: 36, email:'peter@abc.com'}, 
{name: 'john', age: 13, email:'john@abc.com'}, 
] 

我沒有任何鑰匙，但電子郵件l是唯一的

Answer 1

在JavaScript中沒有「更新」方法。

你必須做的，只是簡單地循環你的數組，以檢查對象是否已經在裏面。

function AddOrUpdatePeople(people, person){ 
    for(var i = 0; i< people.length; i++){ 
     if (people[i].email == person.email){ 
      people[i].name = person.name; 
      people[i].age = person.age; 
      return;       //entry found, let's leave the function now 
     } 
    } 
    people.push(person);      //entry not found, lets append the person at the end of the array. 
} 

Answer 2

你也可以通過生成一個Array方法來做到這一點。它有兩個參數。第一個指定要推送的對象，第二個指定要檢查的獨特屬性，以替換之前插入的項目是否存在。

var people = [{name: 'peter', age: 27, email:'peter@abc.com'}]; 
 
Array.prototype.pushWithReplace = function(o,k){ 
 
var fi = this.findIndex(f => f[k] === o[k]); 
 
fi != -1 ? this.splice(fi,1,o) : this.push(o); 
 
return this; 
 
}; 
 
people.pushWithReplace({name: 'John', age: 13, email: 'john@abc.com'}, "email"); 
 
people.pushWithReplace({name: 'peter', age: 36, email: 'peter@abc.com'},"email"); 
 
console.log(people);