Can local variables be accessed outside the functions in which they are declared?

Javascript Get Value Outside Function With Code Examples

Through the use of the programming language, we will work together to solve the Javascript Get Value Outside Function puzzle in this lesson. This is demonstrated in the code that follows.

/*
Scope is important in JavaScript (and probably most
programming languages). If a variable is declared
within a local scope, it can only be accessed from
within that local scope.
*/
function localScope() {
	// this variable is declared locally, it can only
	// be accessed from within this function
	let localVariable = "something";
}
// if you were to try to access localVariable out here
console.log(localVariable); // ReferenceError: 'localVariable' is undefined
// you would not be accessing the variable you declared inside the function

// to get a specific value from a function, you can use
// the return keyword to return a specific value
function add(x, y) {
	return x + y;
}
const two = add(1, 1);

Using numerous real-world examples, we have demonstrated how to fix the Javascript Get Value Outside Function bug.

How do you access a variable outside a function in JavaScript?

To access a variable outside a function in JavaScript make your variable accessible from outside the function. First, declare it outside the function, then use it inside the function. You can't access variables declared inside a function from outside a function.26-May-2022

How do you find the value of the outside of a function?

Using the global statement If you want to assign a value to a name defined outside the function, then you have to tell Python that the name is not local, but it is global. We do this using the global statement. It is impossible to assign a value to a variable defined outside a function without the global statement.

Can you access a variable outside of a function?

In Python and most programming languages, variables declared outside a function are known as global variables. You can access such variables inside and outside of a function, as they have global scope. The variable x in the code above was declared outside a function: x = 10 .10-Jun-2022

Which variable declared outside a function in JavaScript?

JavaScript global variable

How do you access local variables outside?

Variables declared inside a method have method level scope and can't be accessed outside the method. Note : Local variables don't exist after method's execution is over. The above code uses this keyword to differentiate between the local and class variables.28-Jun-2021

How do you access local variables outside the scope?

Local variables cannot be accessed outside the function declaration. Global variable and local variable can have same name without affecting each other.

What is $scope in JavaScript?

Scope in JavaScript refers to the current context of code, which determines the accessibility of variables to JavaScript. The two types of scope are local and global: Global variables are those declared outside of a block. Local variables are those declared inside of a block.20-Feb-2018

What is globalThis?

The globalThis property provides a standard way of accessing the global this value (and hence the global object itself) across environments. Unlike similar properties such as window and self , it's guaranteed to work in window and non-window contexts.11-Sept-2022

What is strict mode in JavaScript?

JavaScript's strict mode is a way to opt in to a restricted variant of JavaScript, thereby implicitly opting-out of "sloppy mode". Strict mode isn't just a subset: it intentionally has different semantics from normal code.22-Sept-2022

What is the variable defined outside a function?

Variables defined outside a function They are called global variables and their scope is global. Variables defined inside a function are local variables.

Local Variables

All the variables we have used thus far have been local variables.  A local variable is a variable which is either a variable declared within the function or is an argument passed to a function.  As you may have encountered in your programming, if we declare variables in a function then we can only use them within that function.  This is a direct result of placing our declaration statements inside functions.

Consider a program that calls a swap() function.

#include <iostream.h>

void swap(int x, int y) {
  int temp = x;
  x = y;
  y = temp;
}

int main()
{
  int A, B;

  cin >> A >> B;

  cout << "A: " << A << "." << endl;
  cout << "B: " << B << "." << endl;
  swap(A, B);
  cout << "A: " << A << "." << endl;
  cout << "B: " << B << "." << endl;

  return 0;
}

Consider variables which are in scope (DEF: portion of a program in which a
variable is legally accessible) in the main() and swap() functions:
 

Function Accessible variables
main A, B
swap temp, x, y

If you attempted to use A was in swap(), a compilation error would result ("undeclared identifier") since it is a local variable in only main().
 

Global Variables

A global variable (DEF) is a variable which is accessible in multiple scopes.  It is important to note that global variables are only accessible after they have been declared.  That is, you can use a variable is is declared below its usage in the text.  For instance, if we consider this simple program, we have one global variable, w.

#include <iostream.h>

double w;

void Z() {
  w = 0;
  return;
}

void Q() {
  int index;

  w = 2;
  return;
}

int main() {
  int i;

  w = 4;

  return 0;
}

w is a global variable which is in scope in all three functions in this program: Z(), Q(), and main().  This program also has local variables: index is local to Q(), and i is local to main().

Scoping can viewed easily in the following table.

Function Accessible Variables
main w, i
Z w
Q w, index

Another example.

#include <iostream.h>

int sum;

void Z(int alpha) {
  sum += 1;
  alpha *= 3;

  return;
}

double total;

void Q() {
  int index;

  total = index;

  return;
}

int main() {
  int i;
  int w = 10;

  sum = 0;
  total = 0;

  return 0;
}

We construct the scoping table.
 

Function Accessible Variables
main sum total, i, w
Q sum, total, index
Z sum, alpha

Note that since the variable total is declared below Z() in the text, total is not in scope in Z().

WARNING

Global variables are not generally used.  It is a contradiction of modularity to have variables be accessible in functions in which they are not used.  In the previous example, sum is not used in Q() even though it is in scope.  If there is a situation where one can justify using a global variable, then it is acceptable.

Can local variables be accessed outside the function?

Variables declared inside any function with var keyword are called local variables. Local variables cannot be accessed or modified outside the function declaration.

How local variables can be accessed?

A local variable is a variable that is declared within a function or it is an argument passed into a function. This means that you can only access these variables in that specific function where they are declared or passed in as an argument.

Can we access local variable outside the block?

You can't access local variable outside the function.

Which variables can be accessed outside a function?

Variables defined outside a function are […] called global variables. Variables defined within a function are local variables. “Scope” is just a technical term for the parts of your code that have access to a variable.