Setinterval() function in nodejs

The setInterval() function in Node.js schedules for a function to be repeatedly executed at specific intervals of time. It makes tasks like background processing, data updates, and periodic checks easier. In spite of its asynchronous nature, it ensures non-blocking execution, which is necessary for maintaining applications responsive. Its callback function can do a number of tasks, and its delay parameter sets the time between executions, which is typically measured in milliseconds. In order to avoid issues with performance and ensure the reliability of the application, careful resource management and error handling are essential. Developers can implement scalable and effective periodic task scheduling for Node.js applications by using setInterval() function.

Syntax:

It has the following syntax:

Parameters:

• const intervalId: The ID of the interval produced by setInterval() is declared as a constant variable in this line, intervalId. Afterward, if required, the interval can be canceled using clearInterval() and the interval ID.
• setInterval (func, [arg1, arg2,..., argN]): It calls the method setInterval(). Using the optional arguments arg1 through argN passed to func on each invocation, it schedules the repeated execution of the function func at intervals indicated by delay.
  1. func: The function that has to be executed repeatedly at the specified intervals.
  2. delay: The time interval (in milliseconds) between each execution of the func.
  3. arg1, arg2, ..., argN (optional): Additional arguments (if any) to be passed to the func on each invocation.

Example-1:

Let us take an example to demonstrate the setInterval() function in Node.js.

Output:

 
HII WORLD
HII WORLD
HII WORLD
HII WORLD
HII WORLD
HII WORLD
HII WORLD
HII WORLD
HII WORLD
HII WORLD
HII WORLD
HII WORLD
HII WORLD.....

Explanation:

In this example, this code sample uses JavaScript's setInterval() method to run an anonymous arrow function repeatedly. This function logs the string "HII WORLD" to the console using an arrow. The 500-millisecond intervals at which this arrow function is set to run are determined by the setInterval() function. It means that unless the interval is explicitly cleared or the program terminates, "HII WORLD" is displayed on the console once every half-second. For JavaScript applications, this method is frequently used to ensure repeating and consistent behavior by executing periodic tasks or updates.

Example-2:

Let us take another example to demonstrate the setInterval() function in Node.js.

Output:

 
HII WORLD
HII WORLD
After two executions, the interval id is cleared.

Explanation:

In this example, a variable named "c" is initialised to 0 in order to track the number of executions. The setInterval() function is then called, and it proceeds with executing an arrow function every 500 milliseconds. The values of "c" and "HII WORLD" are increased within the arrow function. The use of clearInterval(intervalId) to remove the interval ID stops further executions after the second execution (c === 2). This pattern not only demonstrates how to repeat a task using setInterval(), but it also provides a condition that will end the repetition after a set number of iterations.

Example-3:

Let us take another example to sstrate the setInterval() function in Node.js.

Output:

 
The sum of 5 and 5 is 10
The sum of 5 and 5 is 10
The sum of 5 and 5 is 10
After three executions, clearing the interval.

Explanation:

In this example, the SetInterval() in Node.js is used to create a repeating task. With each execution, a counter "c" is increased. It creates a function called intervalFunction that logs and computes the sum of two supplied values. After that, the intervalFunction function is used to call the setInterval() method, sending parameters 5 and 5 to it and defining a 500 millisecond time interval. Clearing the interval with clearInterval(intervalId) is the next step if intervalFunction runs three times. This pattern demonstrates how to carry out an operation repeatedly with an optional condition that stops the operation after a predetermined number of repetitions.