Difficulty encountered when assigning a value to an array within an object derived from a class

Within my Angular project, I've created a class:

export class Test {
  mcq: { question: string, options:string[]}[] = [];
} //outline of an object containing a question and an array of strings

In another component where I import this class, I want to create an object from the Test class. Here's how I did it:

let exampleTest = new Test();
exampleTest.mcq = [{ question: 'any question?', options[0]: 'a', options[1]: 'b', options[2]: 'c', options[3]: 'd'}]

The options[0] part within exampleTest.mcq is causing an error.

I've been spending the last hour trying to figure out what I'm doing wrong. I even attempted

exampleTest.mcq.options[0] = 'a';
but it still doesn't work.

Answer №1

The issue lies in the method of constructing the array for the options within your exampleTest.mcq object. Your current approach appears as follows:

{ options[0]: 'a', options[1]: 'b', options[2]: 'c' }

This is incorrect syntax for creating an array inside an object. What you actually need is

{ options: ['a', 'b', 'c'] }

The code snippet above will assign an array of strings to the key options, which aligns with your intended outcome.

To summarize, use the following code to construct the exampleTest.mcq:

let exampleTest = new Test();
exampleTest.mcq = [{ question: 'any question?', options: ['a', 'b', 'c'] }];

Answer №2

To form an array within an object, the correct syntax is as follows:

{ query: 'Is this a question?', choices: [ 'a', 'b', 'c', 'd' ] }
– Regards: @Jeff Mercado

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