Find object by property in JSON array

问题

I have problem with get string in JSON data. Format as below:

[
  {
    "name": "Alice",
    "age": "20"
  },
  {
    "id": "David",
    "last": "25"
  },
  {
    "id": "John",
    "last": "30"
  }
]

Sometime it changes position together, John from 3rd place go to 2nd place:

[
  {
    "name": "Alice",
    "age": "20"
  },
  {
    "name": "John",
    "age": "30"
  },
  {
    "name": "David",
    "age": "25"
  }
]

If i use data[3].age to get John's age, and data change position, I will get David's age.

Is there any method I can use to find the object with name David and get the age value?

回答1:

You can use array.find() method as,

var myArray = [
  {
    "name": "Alice",
    "age": "20"
  },
  {
    "name": "John",
    "age": "30"
  },
  {
    "name": "David",
    "age": "25"
  }
];

//Here you are passing the parameter name and getting the age 
//Find will get you the first matching object
var result = myArray.find(t=>t.name ==='John').age;
console.log(result);

回答2:

It's better to use array.filter() (better browser support)

myArray.filter(function(el){return el.name == "John"})[0].age

来源：https://stackoverflow.com/questions/50196745/find-object-by-property-in-json-array