Access a javascript object value

Question

Im trying to use a JavaScript object reference to dynamically call different values of an array. Here is tje code i have

//A static call to the object that works and retutns a value
var sam = (obj.Matt); 
console.log(sam)

However, if i do something like this, I am returned an undefined variable from the console log. Theoretically, the variable trent will change based on key in array.

//A dynamic reference
var trent = "Matt";
var sam = obj.trent

score 5 · Answer 1 · edited Oct 27 '17 at 18:01

5

Change this:

var sam = obj.trent   // "dot notation"

to this:

var sam = obj[trent]; // array index notation

Because variables can't be used in standard "dot notation", but they can be used to pass a string into an object and look up the property (key) with that string name.

edited Oct 27 '17 at 18:01

mplungjan

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answered Oct 27 '17 at 17:58

Scott Marcus

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don't forget the quotes: var sam = obj['Trent']; – pro Oct 27 '17 at 18:00
Faster to find one of the 10or more dupes than to answer @pro you are wrong – mplungjan Oct 27 '17 at 18:00
1

@pro No. You don't put quotes there. That's the point. `trent` is a variable that holds a string. – Scott Marcus Oct 27 '17 at 18:01

Access a javascript object value

1 Answers1