Q
How can you log formatted messages with variable values using console.log()?

Answer & Solution

Answer: Option Option A
Solution:
You can log formatted messages with variable values using console.log() by using special symbols like %s and %d in the message string. These symbols act as placeholders for variables or expressions, allowing you to insert dynamic content into log messages. For example, console.log('Name:', name, 'Age:', age); will log 'Name: John Age: 30' to the console with variable values substituted in the message. Using backticks or concatenation directly in the parentheses is not necessary for formatting log messages with variable values, as the special symbols in console.log() handle the formatting and substitution automatically.
Related Questions on Average

What type of information can be logged using console.log() in JavaScript?

A). Only strings and text-based data.

B). Strings, numbers, objects, arrays, and other data types.

C). Numbers and mathematical calculations.

D). Images and multimedia content.

How does console.log() impact the accessibility of a webpage?

A). It improves accessibility by providing interactive elements.

B). It has no impact on accessibility.

C). It may negatively impact accessibility for users with disabilities.

D). It optimizes page performance for accessibility features.

How does console.log() handle logging objects with nested properties?

A). It prints only the top-level properties of the object.

B). It converts the object and all nested properties into string representations.

C). It displays an error message for objects with nested properties.

D). It ignores nested properties and logs the object structure only.

How can you log messages with different log levels using console.log()?

A). By using conditional statements to differentiate log levels.

B). By passing a log level as an argument to console.log().

C). By using multiple console.log() methods with different names.

D). By including log level prefixes in the message strings.

What is the recommended approach for handling console logs in production code?

A). Disable all console logs in production code.

B). Include detailed console logs for all scenarios.

C). Use conditional logging and minimize excessive logging.

D). Log all errors and exceptions using console.error().

What is the behavior of console.log() when logging null or empty values?

A). It logs an empty string for null values and does not log empty values.

B). It logs 'null' or 'undefined' for null or empty values, respectively.

C). It ignores null or empty values and logs the rest of the message.

D). It displays an error message for null or empty values.

What is the recommended approach for logging asynchronous operations using console.log()?

A). Use separate console.log() statements for each asynchronous operation.

B). Include all asynchronous logs within a single console.log() statement.

C). Disable logging for asynchronous operations.

D). Use console.error() for all asynchronous logs.

What is the purpose of using console.log() for debugging JavaScript code?

A). To optimize code execution.

B). To log errors and exceptions.

C). To display messages to users.

D). To track variables, values, and program flow.

What does console.log() output when logging an undefined variable?

A). An empty string.

B). 'undefined'

C). null

D). An error message.

How can you format log messages using console.log() to include variable values or expressions?

A). By using special symbols like %s and %d in the message string.

B). By enclosing expressions in backticks (`) within the message.

C). By concatenating variables directly in the parentheses.

D). By assigning expressions to separate log methods.