Javascript: How to find key name in array of objects -


this question has answer here:

i trying determine if key name present in array of object. example, how verify if key name of 'name' equals argument passed in function call? below code further clarify.

var stooges = [{name: 'moe', age: 40}, {name: 'larry', age: 50}, {name: 'curly', age: 60}]; var test = function(arr, propname){ var result = []; for(var = 0; < arr.length; i++){     if(arr[i][propname] === propname){         result.push(arr[i][propname]);     } } return result; }  func(stooges, "name");

using underscore.js:

var names = _.pluck(stooges, 'name');

in fact example given on page?!

so, on basis knew this, want know how write similar:

function pluck(array, prop]) {     return array.map(function(entry) {         return entry[prop];     }); }

or more safely, returning empty array if initial array undefined:

function pluck(array, prop]) {     return array ? array.map(function(entry) {         return entry[prop];     }) : []; }

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