Javascript对象变量对控制台/页面上的字符串的引用

Question

Ok so i have this code.

var Objectmary={firstName:"mary",lastName:"marshall"};
var Objectjoseph={firstName:"joseph",lastName:"marshall"};
var Objectguy={firstName:"guy", lastName:"steele"};
var contacts=[Objectmary,Objectjoseph,Objectguy];

Basically i want the array contacts to be printed out to either the console, or the page. However if i use

console.log(contacts)

it does not print out the array as [mary,joseph,guy], instead it gives me the object keys and values beside the position in the array.

I just want to print out Objectmary,Objectjoseph,Objectguy to the console or on the page.

Answer 1

Try using Array.prototype.forEach() to iterate objects, console.log() objects firstName property; use Array.prototype.map() to return array containing only firstName properties of objects

 var Objectmary = { firstName: "mary", lastName: "marshall" }; var Objectjoseph = { firstName: "joseph", lastName: "marshall" }; var Objectguy = { firstName: "guy", lastName: "steele" }; var contacts = [Objectmary, Objectjoseph, Objectguy]; contacts.forEach(function(obj) { console.log(obj.firstName, obj.lastName); document.body.innerHTML += obj.firstName + " " + obj.lastName + "<br>" }); var names = contacts.map(function(obj) { return obj.firstName }); console.log(names); 

Answer 2

var Objectmary   = { firstName: 'mary', lastName: 'marshall' },
    Objectjoseph = { firstName: 'joseph', lastName: 'marshall' },
    Objectguy    = { firstName: 'guy', lastName: 'steele' },
    contacts     = [Objectmary, Objectjoseph, Objectguy],
    array_string = '[';

for (var i = 0, l = contacts.length; i < l; i++) {
    array_string += contacts[i].firstName;
    if (i < (l - 1)) array_string += ', '; 
}
array_string += ']';
console.log(array_string);