Answer & Solution
var, let, or const, globalVar becomes a global variable and is accessible anywhere.
console.log(globalVar); if globalVar = 'Hello'; is assigned inside a function without using var, let, or const?
var, let, or const, globalVar becomes a global variable and is accessible anywhere.
What is the global object in a browser environment?
A). window
B). global
C). document
D). this
What will be the output of console.log(window.myVar); if var myVar = 'Hello'; is declared outside any function?
A). Hello
B). undefined
C). error
D). null
How can you avoid global scope pollution?
A). By using local variables
B). By using IIFE (Immediately Invoked Function Expressions)
C). By using modules
D). All of the above
Which of the following methods can help in avoiding global variables?
A). Using functions to encapsulate code
B). Using objects to namespace code
C). Using ES6 modules
D). All of the above
Which statement is true about global variables in JavaScript?
A). They are not accessible inside functions
B). They can be accessed and modified from any part of the code
C). They are constants
D). They can only be read, not modified
Which of the following can create a global variable?
A). var
B). let
C). const
D). All of the above
What is the purpose of the global object in JavaScript?
A). To store local variables
B). To provide a namespace for global variables and functions
C). To define constants
D). To execute code in strict mode
Can a global variable be accessed inside a function?
A). Yes
B). No
C). Only if passed as a parameter
D). Only if defined with var
What happens if you declare a variable inside a function with the same name as a global variable?
A). It creates a new local variable
B). It throws an error
C). It modifies the global variable
D). It assigns the global variable to null
What is the output of console.log(window.globalLet); if let globalLet = 'Hello'; is declared in the global scope?
A). Hello
B). undefined
C). error
D). null