JavaScript For Loop

In JavaScript, the for loop is a control flow statement that allows you to execute a block of code repeatedly for a specific number of iterations. It is commonly used when you know the exact number of times you want the loop to run.

The syntax of a for loop is as follows:

for (initialization; condition; iteration) {

  // code to be executed

}

Here's how a for loop works:

1. The initialization statement is executed before the loop starts. It typically initializes a variable used as a counter.

2. The condition is evaluated before each iteration of the loop. If the condition is true, the code block inside the loop is executed. If the condition is false, the loop is exited, and the program continues with the next statement after the loop.

3. After executing the code block, the iteration statement is executed. It typically updates the counter or performs any other necessary operations.

4. The program then returns to the beginning of the loop, re-evaluates the condition, and repeats the process as long as the condition remains true.

Here's an example of a for loop that counts from 1 to 5:

for (var i = 1; i <= 5; i++) {

  console.log(i);

}

In the example above:

• The i variable is initialized to 1 (var i = 1).

• The condition i <= 5 is checked. If it is true, the code block inside the loop is executed.

• After each iteration, the i variable is incremented by 1 (i++).

• The loop continues executing as long as i is less than or equal to 5.

• Once i becomes 6 and the condition i <= 5 evaluates to false, the loop is exited, and the program continues with the next statement after the loop.

The output of the example will be:

1

2

3

4

5

The for loop is particularly useful when you know the number of iterations in advance, such as iterating over arrays or performing a set number of calculations. It provides a concise and structured way to control the flow of the loop based on initialization, condition, and iteration statements.