JavaScript Object Properties Quiz

Questions and Answers

Which method correctly assigns the string 'apple' to the 'name' property of the 'fruits' object?

fruits.name = 'apple'; (correct)

fruits[name] = 'apple';

fruits['name'] = apple;

fruits.name = apple;

What is the error in the code: 'fruits.name = apple;'?

The variable 'apple' is not declared. (correct)

The property 'name' is not accessed correctly.

All options are correct.

'apple' is not a valid string.

Which of the following lines would result in undefined behavior?

fruits['name'] = 'apple';

fruits['name'] = apple; (correct)

fruits[name] = 'apple'; (correct)

fruits.name = 'apple';

Which code line demonstrates the incorrect use of property assignment?

<p>fruits[0] = 'apple';</p> Signup and view all the answers

Which statement is true regarding the options provided?

<p>Using both dot and bracket notation is acceptable.</p> Signup and view all the answers

Study Notes

Adding Properties to Objects in JavaScript

An object is a fundamental data structure in JavaScript, allowing the storage of key-value pairs.
To add a new property or update an existing property in an object, you can use dot notation or bracket notation.

Methods to Assign a Value to a Property

Using bracket notation: fruits['name'] = 'apple';
- This method uses brackets to specify the property name as a string.
Using dot notation: fruits.name = apple;
- This method uses a dot followed by the property name directly. Ensure the value is enclosed in quotes if it's a string: fruits.name = 'apple';.

Correct Code Options

The correct way to assign the value involves ensuring that the string 'apple' is properly quoted.
The valid options include:
- fruits[name] = 'apple'; (incorrect without quotes around name)
- fruits.name = apple; (incorrect without quotes)
- fruits['name'] = 'apple'; (correct usage)
Options imply an understanding that bracket notation and dot notation can be used interchangeably, depending on the scenario.

Conclusion

The correct way to add a string 'apple' to the property 'name' in the fruits object is to use either bracket notation with quotes or dot notation with correct formatting.

Description

Test your knowledge of JavaScript object properties with this quiz. Focus on understanding how to correctly assign values to object properties using different syntax methods. Choose the right answer to check your understanding.