javascript - 迭代对象值 - javascript

Question

我有以下对象。

{ "name": [ "Can't be blank" ], "league_id": [ "You already have a team in this league." ] }

我想打印这个:

Can't be blank
You already have a team in this league

基本上，我希望能够迭代对象的值。我怎样才能在 JavaScript 中做到这一点？

Answer 1

您的数据结构没有多大实际意义，因为您的属性值是其中只有一个元素的数组。虽然合法，但对于您显示的数据，将字符串作为值更有意义。

无论哪种方式， for/in 遍历对象将允许您迭代键。

当前结构:

let obj = { 
     "name": ["can't be blank"], 
     "league_id": ["You already have a team in this league."] 
};

for(var key in obj){
  console.log(obj[key][0]); // Here, you have to index the property value, which is an array
}

删除数组后:

let obj = { 
     "name": "can't be blank", 
     "league_id": "You already have a team in this league." 
};

for(var key in obj){
  console.log(obj[key]); // Here, you can access the key value directly
}

您还可以使用Object.keys(obj) ，以及 .forEach() 方法调用，这是一种较新的技术:

let obj = { 
     "name": ["can't be blank"], 
     "league_id": ["You already have a team in this league."] 
};

Object.keys(obj).forEach(function(key){
  console.log(obj[key][0]); // Here, you have to index the property value, which is an array
});