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Rye Zhu
5,518 PointsConfused about this part:
Questions about this part:
btn.addEventListener('click', () => {
getJSON(astrosUrl, (json) => {
json.people.map( person => getJSON(wikiUrl + person.name);
});
});
});
What is the json parameter?
What is map?
What about person? person is not a property of people.
as for getJSON(wikiUrl + person.name): what's with the plus sign? I've never seen parameters separated by a plus sign in functions.
Thanks sm. I'm very confused about this chunk of code.
1 Answer
Steven Parker
243,200 PointsIt sounds like you may be taking this course out of order. This is an Intermediate level course, and assumes you are already familiar with most capabilities of the language, such as:
- how to construct an arrow function (both "json" and "person" are arrow function parameters).
- how to use the map method of arrays.
- how to use "+" for string concatenation
If you are new to the language, you might want to start with the Beginning JavaScript track.
If you have some experience already, these courses and workshops might help with your specific questions:
- Introducing Arrow Function Syntax
- JavaScript Array Methods: map()
- JavaScript Basics includes a step about how to Combine Strings
Rye Zhu
5,518 PointsRye Zhu
5,518 Pointsi am taking this course in order as a part of the front end web development track. It's the second to last course of the program. I didn't learn about map(). Did learn about arrow function and string concatenation, but I do not remember learning about "json" and "person". Thank you for the resources. I will check out the workshops to review said materials.