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JavaScript JavaScript Loops, Arrays and Objects Tracking Data Using Objects Using `for in` to Loop Through an Object's Properties

Gavin Ralston
Gavin Ralston
28,770 Points
Posted by Gavin Ralston
Gavin Ralston
28,770 Points

Console output doesn't show array values, just array object

var person = {
  name : 'Sarah',
  country : 'US',
  age : 35,
  treehouseStudent : true,
  skills : ['JavaScript', 'HTML', 'CSS']
};

for (property in person) {
  console.log(property, '= ', person[property]);
}

Chrome console output is slightly different with this than the video. Rather than showing me the array and its contents, I just have an Array object sitting on the line, and the ability to expand it to see the contents.

Is that a change in the console, or a setting I mucked about with?

image of console

2 Answers

Alex Friant
Alex Friant
6,444 Points
Alex Friant
Alex Friant
6,444 Points

Yeah, it might have something to do with Windows vs. Mac.

Anyways, another thing you can do to output JSON is pass it using "JSON.stringify()".

for (property in person) {
  console.log(property, '= ', JSON.stringify(person[property]));
}
Iain Simmons
MOD
Iain Simmons
Treehouse Moderator 32,305 Points
Iain Simmons
Iain Simmons
Treehouse Moderator 32,305 Points

It's just how the Chrome console displays arrays. In the video, Dave shows how you can use the join method of arrays if you wanted to include the values in the array in a string.

It's actually very useful to be able to access the array in the console like that because you can see all the values, the length property, and even expand the prototype to see the array methods you can use.