Retrieving values from object with array

Question

I am working on method code in which I have to iterate through an json object with dynamic array. my code is like this:

var tableHeaders = ["id", "name", "status"]; 
var item = {
 id: 1,
 name: "test name",
 status: true,
 email: "[email protected]"
} 
console.log(item.id); // works well --> 1 
console.log(tableHeaders[0]); // works well --> id 
console.log(item.tableHeaders[0]); // not works

Here is jsfiddle: http://jsfiddle.net/kslagdive/rjFHV/ Please suggest me, how can I get value of item with Array element? Thanks

Answer 1

Since your property name is dynamic, you have to use bracket notation instead of dot notation:

console.log(item[tableHeaders[0]]); // Works.

Answer 2

It should be...

item[ tableHeaders[0] ];

... that is, using bracket notation to access a property by its name. Note that you use any complex expression here, for example:

item[ 'e' + 'mail' ]; // the same as item.email

• KSL: Yes okay. Got it using bracket notation instead of dot. Thanks.

Answer 3

Need to use [] notation instead of . notation when you use dynamic keys

console.log(item[tableHeaders[0]]);

Demo: Fiddle

• KSL: Got it using bracket notation instead of dot. Thanks.

Answer 4

Tabheaders is not a value of item. Try

var tableHeaders = ["id", "name", "status"]; 
var item = {
 id: 1,
 name: "test name",
 status: true,
 email: "[email protected]",
 tableHeaders: tableHeaders // define "tableHeaders" as value of "item"
} 

Thanks @xec for your comment.

Well the answer is already here but anyway:

var key = tableHeaders[0]; // the key for the value you want to extract from items.
var value = item[key]; // get the value from item based on the key defined 
 // in table headers using the [Bracket notation][1] 
 // (@Frédéric Hamidi).

• xec: I believe he wants 1 returned (the value of the id property)