Control Flow, Loops, Javascript, Programming, Electro4u

Control Flow and Loops in Javascript

Control flow and loops are basic elements of programming. Control Flow is the order in which statements, functions, and other instructions are executed or evaluated. Loops execute a block of code multiple times, until an expression is false.

Control Flow

In Javascript, control flow is managed through the use of conditional statements such as if-else, switch-case and ternary operators. These statements allow you to create blocks of code that will only be executed when certain conditions are met.

If-Else Statement

The if-else statement allows you to check for a condition and then execute different code based on the result. If the condition is true, the code in the 'if' block will be executed, otherwise, the code in the 'else' block will be executed.

  ## Example
  let x = 10;
  if (x > 5) {
    console.log('x is greater than 5');
  } else {
    console.log('x is less than or equal to 5');
  }

Switch-Case Statement

The switch-case statement is a more concise alternative to the if-else statement. It allows you to check for multiple conditions in one place and execute code based on the matched condition.

  ## Example
  let y = 'a';
  switch(y) {
   case 'a':
      console.log('y is a');
      break;
   case 'b':
      console.log('y is b');
      break;
   default:
      console.log('y is something else');
  }

Ternary Operator

The ternary operator is a shorthand version of an if-else statement, which allows you to check a condition and execute different code based on the result. It is typically used in situations where a simple if-else statement would not be sufficient.

  ## Example
  let x = 10;
  (x > 5) ? console.log('x is greater than 5') : console.log('x is less than or equal to 5');

Loops

In Javascript, loops are used to repeat blocks of code multiple times. There are three types of loops available in Javascript: for, while, and do-while.

For Loop

The for loop allows you to execute a block of code multiple times, with an incrementing counter. It is usually used when you know the exact number of iterations you need to perform.

  ## Example
  // print numbers 1 to 10
  for (let i = 1; i <= 10; i++) {
    console.log(i);
  }

While Loop

The while loop allows you to execute a block of code while an expression is true. It is usually used when you don't know the exact number of iterations you need to perform, or when the iterations need to be determined on the fly.

  ## Example
  // print numbers 1 to 10
  let i = 1;
  while (i <= 10) {
    console.log(i);
    i++;
  }

Do-While Loop

The do-while loop is similar to the while loop, except that it executes the body of the loop at least once, regardless of whether the condition is true or false.

  ## Example
  // print numbers 1 to 10
  let i = 1;
  do {
    console.log(i);
    i++;
  } while (i <= 10);

Control flow and loops are essential elements of programming and are commonly used to solve complex problems. With the help of these features, you can write efficient and effective code that can automate tedious tasks and reduce complexity.