javascript - 如何在对象数组中找到具有最长字符长度的对象键

Question

假设我有一个像这样的对象集合

var collection = [
{
     name:"John",
     age:12,
     location:"Califonia",
     gender:"Male"
},
{
     name:"Jane",
     age:18,
     location:"New york",
     gender:"Female"
}
]

很明显“location”是字符长度最长的对象键。

但是我怎样才能动态地得到这个，因为我不知道如何提前构建集合。

Answer 1

具有这些功能:

/**
 * Get the longest key in an object.
 */ 
function longestKey(obj) {
  return Object.keys(obj).reduce(function(all, current) {
    return all.length > current.length ? all : current;
  });
}

/**
 * Get the object with the longest key from array of objects.
 */ 
function longestKeyObj(arr) {
  return arr.reduce(function(all, current) {
    return longestKey(all).length > longestKey(current).length ? all : current;
  });
}

你可以这样做:

const me = {
  name: 'nabil',
  occupation: 'programming',
  dob: '1984-12-28',
};

const you = {
  longestKey: 'blah!',
};

console.log('The object is: ', longestKeyObj([me, you]));
console.log('The key is: ', longestKey(longestKeyObj([me, you])));

哪些输出:

The object is: { longestKey: 'blah!' }

The key is: longestKey

演示:https://repl.it/@kadimi/longestKey