In JavaScript, a value is considered undefined if it has not been assigned a value or if it has been explicitly set to undefined. There are several ways to check if a value is undefined in JavaScript: typeof operator: The typeof operator returns a string indicating the type of the operand. If the operand is…
In JavaScript, `undefined` is a primitive value that represents the absence of a value. It is often used to initialize variables before they are assigned a value, or to represent the return value of a function that does not return a value. There are several ways to check if a variable is `undefined` in JavaScript….
In programming, a variable is a container that stores data. In JavaScript, a variable can be declared using the keyword `let` or `const`. If a variable is not declared, it is considered undefined. There are several ways to check if a variable is undefined in JavaScript. One way to check if a variable is undefined…
