javascript - accessing specific data in an array of objects

Question

How do I pick the first value of rowVal of the first object (I want to print 42.00).

dataTest.rows = [{
  "rowHeader": "",
  "rowDesc": ["Gene Name"],
  "rowVal": [
    ["42.00", "57.00", "45.00", "48.00", "52.00", "47.00", "39.00", "38.00", "35.00"]
  ]
}, {
  "rowHeader": "",
  "rowDesc": ["Gene Source"],
  "rowVal": [
    ["38.00", "50.00", "39.00", "41.00", "45.00", "40.00", "34.00", "33.00", "29.00"]

  ]
}];

I tried:

console.log(dataTest.rows[0].rowVal[0]);

but it returns all the numbers in the array of rowVal of the first object?

rowVal is an array of arrays, not an array of primitives: you're selecting a sub-array, not a string inside the sub-array. Go down one more level to access the first element: console.log(dataTest.rows[0].rowVal[0][0]); — CertainPerformance
– CertainPerformance, Commented Apr 19, 2018 at 3:37
console.log(dataTest.rows[0].rowVal[0][0]); You were so close. Note the extra [0] — Randy Casburn
– Randy Casburn, Commented Apr 19, 2018 at 3:37
Your rowVal is an array with an array as the first value. Note the [[ — Mark
– Mark, Commented Apr 19, 2018 at 3:37
thank you.. I see.. i am building the code slowly to be able to load a json file into a table.. i still have some work to do before i get there — ApisMel
– ApisMel, Commented Apr 19, 2018 at 3:42

Romeo Sierra · Accepted Answer · 2018-04-19 03:40:26Z

1

rowVal is an Array of Arrays. That's why you get that result.

    "rowVal": [
        ["38.00", "50.00", "39.00", "41.00", "45.00", "40.00", "34.00", "33.00", "29.00"]

    ]

See, when you say rowVal[0], it refers to an array. So, ideally, it should be something like

    "rowVal": ["38.00", "50.00", "39.00", "41.00", "45.00", "40.00", "34.00", "33.00", "29.00"]

if you want to access the elements as rowVal[0]. Or else, you have to change your reference to rowVal[0][0].

answered Apr 19, 2018 at 3:40

Romeo Sierra

1,7862 gold badges19 silver badges39 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

javascript - accessing specific data in an array of objects

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related