制作嵌套对象数组并检查objs中是否存在该键

Question

I am trying to check if the keys exits in array of objects. I am getting false each time when I pass existing key to my function.

var connect_clients = [];
connect_clients.push({
  'a': val
});

function lookup(name) {
  for (var i = 0, len = connect_clients.length; i < len; i++) {
    if (connect_clients[i].key === name)
      return true;
  }
  return false;
}

console.log(lookup('a'));

Is there anything wrong?

Answer 1

connect_clients[i].key refers to the actual property named key , not the keys of the object.

For this case, you can use Object.keys to get an array of keys of an object and use Array.prototype.some to make sure that at least one of the objects has the key. For example,

function lookup(name) {
  return connect_clients.some(function(client) {
    return Object.keys(client).indexOf(name) !== -1;
  });
}

Answer 2

Use Object.keys() to get keys of an object.

var val = 'val';
var connect_clients = [];

connect_clients.push({
  'a': val
});

function lookup(keyName) {
    var i;

    for ( i = 0; i < connect_clients.length; i++) {
        var keys = Object.keys(connect_clients[i]);

        if(keys.indexOf(keyName) !== -1) {
            return true;
        }
    }

    return false;
}

console.log(lookup('a'));